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Mbah GE, Ayiseh RB, Monya E, Ndi EM, Njotu FN, Kulu TK, Sakanari J, Lustigman S, Cho-Ngwa F. Differential susceptibility of Onchocerca ochengi adult male worms to flubendazole in gerbils and hamsters. Parasitol Res 2024; 123:186. [PMID: 38634933 DOI: 10.1007/s00436-024-08207-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 04/09/2024] [Indexed: 04/19/2024]
Abstract
Onchocerciasis is a devastating skin and eye disease that afflicts about 21 million people, most of whom live in sub-Saharan Africa. Its control with the microfilaricidal drug ivermectin is limited, thus necessitating the development of preclinical animal models to aid in the discovery of a macrofilaricide. Previously, we found that Onchocerca ochengi (the closest relative of the human O. volvulus) worm masses survive better in hamsters than in gerbils. The aim of this study was to compare the survival of O. ochengi adult male worms and their susceptibility to flubendazole (FBZ, a macrofilaricide) in gerbils and hamsters. The animals were intraperitoneally implanted with O. ochengi male worms, treated with FBZ, and sacrificed 35 days post-implantation. Unlike gerbils which had some worms moving freely in the peritoneum and some in newly formed nodules (neo-nodules), all the worms in the hamsters were found in neo-nodules. FBZ significantly decreased worm burden, motility, and viability in gerbils whereas it had no significant effect in hamsters. These results highlight a major difference in how O. ochengi adult male worms are sustained and affected by FBZ in gerbils compared to hamsters. Understanding the difference between these two models is important in the development of effective macrofilaricides for onchocerciasis.
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Affiliation(s)
- Glory Enjong Mbah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
- Department of Biology, Higher Teacher Training College (HTTC), The University of Bamenda, Bamenda, Cameroon
- National Higher Polytechnic Institute (NAHPI), The University of Bamenda, Bamenda, Cameroon
| | - Rene Bilingwe Ayiseh
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon.
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, Cameroon.
| | - Elvis Monya
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Emmanuel Menang Ndi
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Fabrice Ngoh Njotu
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Tessy-Koko Kulu
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Sara Lustigman
- New York Blood Center, Lindsley F. Kimball Research Institute, New York City, NY, USA
| | - Fidelis Cho-Ngwa
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon.
- National Higher Polytechnic Institute (NAHPI), The University of Bamenda, Bamenda, Cameroon.
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Hegde S, Marriott AE, Pionnier N, Steven A, Bulman C, Gunderson E, Vogel I, Koschel M, Ehrens A, Lustigman S, Voronin D, Tricoche N, Hoerauf A, Hübner MP, Sakanari J, Aljayyoussi G, Gusovsky F, Dagley J, Hong DW, O'Neill P, Ward SA, Taylor MJ, Turner JD. Combinations of the azaquinazoline anti- Wolbachia agent, AWZ1066S, with benzimidazole anthelmintics synergise to mediate sub-seven-day sterilising and curative efficacies in experimental models of filariasis. Front Microbiol 2024; 15:1346068. [PMID: 38362501 PMCID: PMC10867176 DOI: 10.3389/fmicb.2024.1346068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 01/02/2024] [Indexed: 02/17/2024] Open
Abstract
Lymphatic filariasis and onchocerciasis are two major neglected tropical diseases that are responsible for causing severe disability in 50 million people worldwide, whilst veterinary filariasis (heartworm) is a potentially lethal parasitic infection of companion animals. There is an urgent need for safe, short-course curative (macrofilaricidal) drugs to eliminate these debilitating parasite infections. We investigated combination treatments of the novel anti-Wolbachia azaquinazoline small molecule, AWZ1066S, with benzimidazole drugs (albendazole or oxfendazole) in up to four different rodent filariasis infection models: Brugia malayi-CB.17 SCID mice, B. malayi-Mongolian gerbils, B. pahangi-Mongolian gerbils, and Litomosoides sigmodontis-Mongolian gerbils. Combination treatments synergised to elicit threshold (>90%) Wolbachia depletion from female worms in 5 days of treatment, using 2-fold lower dose-exposures of AWZ1066S than monotherapy. Short-course lowered dose AWZ1066S-albendazole combination treatments also delivered partial adulticidal activities and/or long-lasting inhibition of embryogenesis, resulting in complete transmission blockade in B. pahangi and L. sigmodontis gerbil models. We determined that short-course AWZ1066S-albendazole co-treatment significantly augmented the depletion of Wolbachia populations within both germline and hypodermal tissues of B. malayi female worms and in hypodermal tissues in male worms, indicating that anti-Wolbachia synergy is not limited to targeting female embryonic tissues. Our data provides pre-clinical proof-of-concept that sub-seven-day combinations of rapid-acting novel anti-Wolbachia agents with benzimidazole anthelmintics are a promising curative and transmission-blocking drug treatment strategy for filarial diseases of medical and veterinary importance.
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Affiliation(s)
- Shrilakshmi Hegde
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Amy E. Marriott
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nicolas Pionnier
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Andrew Steven
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Christina Bulman
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, Unites States
| | - Emma Gunderson
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, Unites States
| | - Ian Vogel
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, Unites States
| | - Marianne Koschel
- Department of Immunology and Parasitology, Institute for Medical Microbiology, University Hospital Bonn, Bonn, Germany
| | - Alexandra Ehrens
- Department of Immunology and Parasitology, Institute for Medical Microbiology, University Hospital Bonn, Bonn, Germany
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, Unites States
| | - Denis Voronin
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, Unites States
| | - Nancy Tricoche
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, Unites States
| | - Achim Hoerauf
- Department of Immunology and Parasitology, Institute for Medical Microbiology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Marc P. Hübner
- Department of Immunology and Parasitology, Institute for Medical Microbiology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, Unites States
| | - Ghaith Aljayyoussi
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Jessica Dagley
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - David W. Hong
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Paul O'Neill
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - Steven A. Ward
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Mark J. Taylor
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Joseph D. Turner
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Geary TG. New paradigms in research on Dirofilaria immitis. Parasit Vectors 2023; 16:247. [PMID: 37480077 PMCID: PMC10362759 DOI: 10.1186/s13071-023-05762-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/30/2023] [Indexed: 07/23/2023] Open
Abstract
BACKGROUND Since the advent of ivermectin (along with melarsomine and doxycycline), heartworm has come to be viewed as a solved problem in veterinary medicine, diminishing investment into non-clinical research on Dirofilaria immitis. However, heartworm infections continue to pose problems for practitioners and their patients and seem to be increasing in frequency and geographic distribution. Resistance to preventative therapies (macrocyclic lactones) complicates the picture. The use of chemotherapy for other kinds of pathogens has benefitted enormously from research into the basic biology of the pathogen and on the host-pathogen interface. A lack of basic information on heartworms as parasites and how they interact with permissive and non-permissive hosts greatly limits the ability to discover new ways to prevent and treat heartworm disease. Recent advances in technical platforms will help overcome the intrinsic barriers that hamper research on D. immitis, most notably, the need for experimentally infected dogs to maintain the life cycle and provide material for experiments. Impressive achievements in the development of laboratory animal models for D. immitis will enhance efforts to discover new drugs for prevention or treatment, to characterize new diagnostic biomarkers and to identify key parasite-derived molecules that are essential for survival in permissive hosts, providing a rational basis for vaccine discovery. A 'genomics toolbox' for D. immitis could enable unprecedented insight into the negotiations between host and parasite that enable survival in a permissive host. The more we know about the pathogen and how it manipulates its host, the better able we will be to protect companion animals far into the future.
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Affiliation(s)
- Timothy G Geary
- Institute of Parasitology, McGill University, Ste-Anne-de-Bellevue, QC, Canada.
- School of Biological Sciences, Queen's University-Belfast, Belfast, Northern Ireland.
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Marriott AE, Dagley JL, Hegde S, Steven A, Fricks C, DiCosty U, Mansour A, Campbell EJ, Wilson CM, Gusovsky F, Ward SA, Hong WD, O'Neill P, Moorhead A, McCall S, McCall JW, Taylor MJ, Turner JD. Dirofilariasis mouse models for heartworm preclinical research. Front Microbiol 2023; 14:1208301. [PMID: 37426014 PMCID: PMC10324412 DOI: 10.3389/fmicb.2023.1208301] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 05/30/2023] [Indexed: 07/11/2023] Open
Abstract
Introduction Dirofilariasis, including heartworm disease, is a major emergent veterinary parasitic infection and a human zoonosis. Currently, experimental infections of cats and dogs are used in veterinary heartworm preclinical drug research. Methods As a refined alternative in vivo heartworm preventative drug screen, we assessed lymphopenic mouse strains with ablation of the interleukin-2/7 common gamma chain (γc) as susceptible to the larval development phase of Dirofilaria immitis. Results Non-obese diabetic (NOD) severe combined immunodeficiency (SCID)γc-/- (NSG and NXG) and recombination-activating gene (RAG)2-/-γc-/- mouse strains yielded viable D. immitis larvae at 2-4 weeks post-infection, including the use of different batches of D. immitis infectious larvae, different D. immitis isolates, and at different laboratories. Mice did not display any clinical signs associated with infection for up to 4 weeks. Developing larvae were found in subcutaneous and muscle fascia tissues, which is the natural site of this stage of heartworm in dogs. Compared with in vitro-propagated larvae at day 14, in vivo-derived larvae had completed the L4 molt, were significantly larger, and contained expanded Wolbachia endobacteria titres. We established an ex vivo L4 paralytic screening system whereby assays with moxidectin or levamisole highlighted discrepancies in relative drug sensitivities in comparison with in vitro-reared L4 D. immitis. We demonstrated effective depletion of Wolbachia by 70%-90% in D. immitis L4 following 2- to 7-day oral in vivo exposures of NSG- or NXG-infected mice with doxycycline or the rapid-acting investigational drug, AWZ1066S. We validated NSG and NXG D. immitis mouse models as a filaricide screen by in vivo treatments with single injections of moxidectin, which mediated a 60%-88% reduction in L4 larvae at 14-28 days. Discussion Future adoption of these mouse models will benefit end-user laboratories conducting research and development of novel heartworm preventatives via increased access, rapid turnaround, and reduced costs and may simultaneously decrease the need for experimental cat or dog use.
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Affiliation(s)
- A. E. Marriott
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - J. L. Dagley
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - S. Hegde
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - A. Steven
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - C. Fricks
- TRS Laboratories Inc, Athens, GA, United States
| | - U. DiCosty
- TRS Laboratories Inc, Athens, GA, United States
| | - A. Mansour
- TRS Laboratories Inc, Athens, GA, United States
| | - E. J. Campbell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - C. M. Wilson
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - F. Gusovsky
- Eisai Global Health, Cambridge, MA, United States
| | - S. A. Ward
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - W. D. Hong
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - P. O'Neill
- Department of Chemistry, University of Liverpool, Liverpool, United Kingdom
| | - A. Moorhead
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - S. McCall
- TRS Laboratories Inc, Athens, GA, United States
| | - J. W. McCall
- TRS Laboratories Inc, Athens, GA, United States
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - M. J. Taylor
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - J. D. Turner
- Department of Tropical Disease Biology, Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
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Ayiseh RB, Mbah GE, Manfo FPT, Kulu TK, Njotu FN, Monya E, Ndi EM, Tumanjong IM, Mainsah EN, Sakanari J, Lustigman S, Cho-Ngwa F. Survival of worm masses of Onchocerca ochengi in gerbils and hamsters: implications for the development of an in vivo macrofilaricide screening model. Parasitol Res 2023:10.1007/s00436-023-07859-7. [PMID: 37154921 DOI: 10.1007/s00436-023-07859-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/27/2023] [Indexed: 05/10/2023]
Abstract
Onchocerciasis, the second leading infectious cause of blindness, afflicts approximately 21 million people globally. Its control is limited to the use of the microfilaricidal drugs, ivermectin and moxidectin. Both drugs are unable to kill the adult worms which can survive for up to 15 years in patients, justifying the urgent need for potent and novel macrofilaricides that kill adult worms. The development of such drugs has been hindered by the lack of an appropriate small laboratory animal model to evaluate potential drug candidates in vivo. This study assessed the survival of O. ochengi female worms and their embryos over time in two laboratory rodents: gerbils and hamsters and tested using "proof-of-concept" studies, whether known macrofilaricidal drugs can kill these worms. Animals were surgically implanted with mechanical or collagenase-liberated O. ochengi worm masses, and necropsied at various time points to test for survival. Recovered worm masses were assessed for viability by biochemical analysis (MTT/formazan assay) or fecundity (embryogram). Flubendazole (FBZ) administered at 20 mg/kg body weight was used to validate both rodent models. By day 26 post-implantation of 15 worm masses, a median of 7.00 (4.00-10.00) was recovered from hamsters, and 2.50 (2.00-4.00) from gerbils. Worm masses recovered from gerbils were mostly disintegrated or fragmented, with significantly higher fragmentation observed with collagenase-liberated worm masses. FBZ had no significant effect on the number of worm masses recovered, but enhanced embryo degradation in gerbils and reduced worm mass viability in hamsters. This exploratory study has revealed the gerbil and hamster as permissible rodents to adult female worms of O. ochengi. The hamsters appeared to maintain the worms longer, compared to gerbils.
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Affiliation(s)
- Rene Bilingwe Ayiseh
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon.
| | - Glory Enjong Mbah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
- Department of Biology, Higher Teacher Training College (HTTC), The University of Bamenda, Bambili, Cameroon
- National Higher Polytechnic Institute (NAHPI), The University of Bamenda, Bambili, Cameroon
| | - Faustin Pascal Tsague Manfo
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Tessy-Koko Kulu
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Fabrice Ngoh Njotu
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Elvis Monya
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Emmanuel Menang Ndi
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Irene Memeh Tumanjong
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Evans Ngandung Mainsah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Sara Lustigman
- New York Blood Center, Lindsey F. Kimball Research Institute, New York City, NY, USA
| | - Fidelis Cho-Ngwa
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon.
- National Higher Polytechnic Institute (NAHPI), The University of Bamenda, Bambili, Cameroon.
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Ayiseh RB, Mbah GE, Monya E, Ndi EM, Sakanari J, Lustigman S, Cho-Ngwa F. Development and validation of small animal models for onchocerciasis and loiasis microfilaricide discovery. PLoS Negl Trop Dis 2023; 17:e0011135. [PMID: 36827447 PMCID: PMC9994675 DOI: 10.1371/journal.pntd.0011135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 03/08/2023] [Accepted: 02/01/2023] [Indexed: 02/26/2023] Open
Abstract
BACKGROUND Onchocerciasis (river blindness) caused by the filarial worm Onchocerca volvulus is a neglected tropical disease that affects the skin and eyes of humans. Mass drug administration with ivermectin (IVM) to control the disease often suffers from severe adverse events in individuals co-injected with high loads of Loa loa microfilariae (mf). Thus loiasis animal models for counter-screening of compounds effective against onchocerciasis are needed, as are the corresponding onchocerciasis screening models. The repertoire of such models is highly limiting. Therefore, this study was aimed at developing and validating mf immunocompetent small animal models to increase tools for onchocerciasis drug discovery. METHODOLOGY/PRINCIPAL FINDINGS O. ochengi mf from cattle skin and L. loa mf from human blood were used to infect BALB/c mice and Mongolian gerbils, and IVM was used for model validation. O. ochengi mf were given subcutaneously to both rodents while L. loa mf were administered intravenously to mice and intraperitoneally to gerbils. IVM was given orally. In an 8-day model of O. ochengi mf in BALB/c mice, treatment with IVM depleted all mf in the mice, unlike the controls. Also, in a 2.5-day model of L. loa mf in BALB/c, IVM significantly reduced mf in treated mice compared to the untreated. Furthermore, the gerbils were very susceptible to O. ochengi mf and IVM eradicated all mf in the treated animals. In the peritoneal L. loa mf gerbil model, IVM reduced mf motility in treated animals compared to the controls. In a 30-day gerbil co-injection model, IVM treatment cleared all O. ochengi mf and reduced motility of L. loa mf. Both mf survived for up to 50 days in a gerbil co-injection model. CONCLUSIONS/SIGNIFICANCE We have developed two immunocompetent small animal models for onchocerciasis and loiasis that can be used for microfilaricide discovery and to counter-screen onchocerciasis macrofilarides.
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Affiliation(s)
- Rene Bilingwe Ayiseh
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Glory Enjong Mbah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Elvis Monya
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Emmanuel Menang Ndi
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, United States of America
| | - Sara Lustigman
- Lindsley F. Kimball Research Institute, New York Blood Center, New York City, New York, United States of America
| | - Fidelis Cho-Ngwa
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
- * E-mail:
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Fordjour FA, Kwarteng A. The filarial and the antibiotics: Single or combination therapy using antibiotics for filariasis. Front Cell Infect Microbiol 2022; 12:1044412. [PMID: 36467729 PMCID: PMC9712956 DOI: 10.3389/fcimb.2022.1044412] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 10/24/2022] [Indexed: 12/01/2023] Open
Abstract
Filarial infections caused by nematodes are one of the major neglected tropical diseases with public health concern. Although there is significant decrease in microfilariae (mf) prevalence following mass drug administration (IVM/DEC/ALB administration), this is transient, in that there is reported microfilaria repopulation 6-12 months after treatment. Wolbachia bacteria have been recommended as a novel target presenting antibiotic-based treatment for filarial disease. Potency of antibiotics against filarial diseases is undoubtful, however, the duration for treatment remains a hurdle yet to be overcome in filarial disease treatment.
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Affiliation(s)
- Fatima Amponsah Fordjour
- Department of Microbiology, University for Development Studies (UDS), Tamale, Ghana
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Alexander Kwarteng
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
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Ehrens A, Hoerauf A, Hübner MP. Eosinophils in filarial infections: Inducers of protection or pathology? Front Immunol 2022; 13:983812. [PMID: 36389745 PMCID: PMC9659639 DOI: 10.3389/fimmu.2022.983812] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/05/2022] [Indexed: 05/29/2024] Open
Abstract
Filariae are parasitic roundworms, which can cause debilitating diseases such as lymphatic filariasis and onchocerciasis. Lymphatic filariasis, also known as elephantiasis, and onchocerciasis, commonly referred to as river blindness, can lead to stigmatizing pathologies and present a socio-economic burden for affected people and their endemic countries. Filariae typically induce a type 2 immune response, which is characterized by cytokines, i.e., IL-4, IL-5 and IL-13 as well as type 2 immune cells including alternatively activated macrophages, innate lymphoid cells and Th2 cells. However, the hallmark characteristic of filarial infections is a profound eosinophilia. Eosinophils are innate immune cells and pivotal in controlling helminth infections in general and filarial infections in particular. By modulating the function of other leukocytes, eosinophils support and drive type 2 immune responses. Moreover, as primary effector cells, eosinophils can directly attack filariae through the release of granules containing toxic cationic proteins with or without extracellular DNA traps. At the same time, eosinophils can be a driving force for filarial pathology as observed during tropical pulmonary eosinophilia in lymphatic filariasis, in dermatitis in onchocerciasis patients as well as adverse events after treatment of onchocerciasis patients with diethylcarbamazine. This review summarizes the latest findings of the importance of eosinophil effector functions including the role of eosinophil-derived proteins in controlling filarial infections and their impact on filarial pathology analyzing both human and experimental animal studies.
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Affiliation(s)
- Alexandra Ehrens
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Marc P. Hübner
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
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9
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Marriott AE, Furlong Silva J, Pionnier N, Sjoberg H, Archer J, Steven A, Kempf D, Taylor MJ, Turner JD. A mouse infection model and long-term lymphatic endothelium co-culture system to evaluate drugs against adult Brugia malayi. PLoS Negl Trop Dis 2022; 16:e0010474. [PMID: 35671324 PMCID: PMC9205518 DOI: 10.1371/journal.pntd.0010474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 06/17/2022] [Accepted: 05/07/2022] [Indexed: 11/18/2022] Open
Abstract
The development of new drugs targeting adult-stage lymphatic filarial nematodes is hindered by the lack of a robust long-term in vitro culture model. Testing potential direct-acting and anti-Wolbachia therapeutic candidates against adult lymphatic filariae in vitro requires their propagation via chronic infection of gerbils. We evaluated Brugia malayi parasite burden data from male Mongolian gerbils compared with two immune-deficient mouse strains highly susceptible to B. malayi: CB.17 Severe-Combined Immmuno-Deficient (SCID) and interleukin-4 receptor alpha, interleukin-5 double knockout (IL-4Rα-/-IL-5-/-) mice. Adult worms generated in IL-4Rα-/-IL-5-/- mice were tested with different feeder cells (human embryonic kidney cells, human adult dermal lymphatic endothelial cells and human THP-1 monocyte differentiated macrophages) and comparative cell-free conditions to optimise and validate a long-term in vitro culture system. Cultured parasites were compared against those isolated from mice using motility scoring, metabolic viability assay (MTT), ex vivo microfilariae release assay and Wolbachia content by qPCR. A selected culture system was validated as a drug screen using reference anti-Wolbachia (doxycycline, ABBV-4083 / flubentylosin) or direct-acting compounds (flubendazole, suramin). BALB/c IL-4Rα-/-IL-5-/- or CB.17 SCID mice were superior to Mongolian gerbils in generating adult worms and supporting in vivo persistence for periods of up to 52 weeks. Adult females retrieved from BALB/c IL-4Rα-/-IL-5-/- mice could be cultured for up to 21 days in the presence of a lymphatic endothelial cell co-culture system with comparable motility, metabolic activity and Wolbachia titres to those maintained in vivo. Drug studies confirmed significant Wolbachia depletions or direct macrofilaricidal activities could be discerned when female B. malayi were cultured for 14 days. We therefore demonstrate a novel methodology to generate adult B. malayi in vivo and accurately evaluate drug efficacy ex vivo which may be adopted for drug screening with the dual benefit of reducing overall animal use and improving anti-filarial drug development.
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Affiliation(s)
- Amy E. Marriott
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Julio Furlong Silva
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Nicolas Pionnier
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Hanna Sjoberg
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - John Archer
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Andrew Steven
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Dale Kempf
- Pharmaceutical R&D, AbbVie, North Chicago, Illinois, United States of America
| | - Mark J. Taylor
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Joseph D. Turner
- Centre for Drugs and Diagnostics & Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
- * E-mail:
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10
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Al-Delaimy AK. The Prospective Effects of Climate Change on Neglected Tropical Diseases in the Eastern Mediterranean Region: a Review. Curr Environ Health Rep 2022; 9:315-323. [PMID: 35286599 DOI: 10.1007/s40572-022-00339-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2022] [Indexed: 11/26/2022]
Abstract
An increase in the annual daily temperature is documented and predicted to occur in the coming decades. Climate change has a direct effect and adverse impact on human health, as well as on multiple ecosystems and their species. The purpose of this paper is to review the effect of climate change on neglected tropical diseases including leishmaniasis, schistosomiasis, and lymphatic filariasis in the Eastern Mediterranean Region (EMR). A list of engine web searches was done; 280 full-text records were assessed for eligibility. Only 48 original records were included within the final selection for the review study. Most research results show an alteration of neglected diseases related to climate change influencing specifically the Eastern Mediterranean Region, in addition to the expectation of more effects at the level of vectors and reservoir whether its vector transmission route or its egg hatching and replication or even the survival of adult worms in the coming years. At the same time, not all articles related to the region interpret the direct or indirect effect of climate variations on these specific diseases. Although few studies were found describing some of climate change effects on neglected tropical diseases in the region, still, the region lacks research funding, technical, and mathematical model expertise regarding the direct effect of climate change on the ecosystems of these neglected tropical diseases.
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Affiliation(s)
- Ahmed K Al-Delaimy
- Family & Community Medicine Department/Anbar Medical College, Anbar University, Ramadi, Iraq.
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11
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Pionnier N, Furlong-Silva J, Colombo SAP, Marriott AE, Chunda VC, Ndzeshang BL, Sjoberg H, Archer J, Steven A, Wanji S, Taylor MJ, Turner JD. NKp46 + natural killer cells develop an activated/memory-like phenotype and contribute to innate immunity against experimental filarial infection. Front Immunol 2022; 13:969340. [PMID: 36238293 PMCID: PMC9551455 DOI: 10.3389/fimmu.2022.969340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/05/2022] [Indexed: 11/13/2022] Open
Abstract
Lymphatic filariasis and onchocerciasis are major neglected tropical diseases affecting over 90 million people worldwide with painful and profoundly disfiguring pathologies (such as lymphoedema or blindness). Type 2 inflammation is a hallmark of filarial nematode tissue infection and is implicated both in eosinophil dependent immunity and lymphatic or ocular immunopathologies. Type-2 innate lymphoid cells (ILC2) are known to play an important role in the initiation of type 2 inflammation in helminth infection. We therefore tracked comparative IL-12Rβ2+ ILC1, ST2+ ILC2 and NKp46+ natural killer (NK) innate lymphoid cell population expansions during Brugia malayi experimental peritoneal filarial infections using either immunocompetent or immunodeficient mice. In immunocompetent BALB/c animals, NKp46+ NK cells rapidly expanded representing over 90% of the ILC population in the first week of infection, whereas, surprisingly, ST2+ ILC2 failed to expand. NKp46+ NK cell expansions were confirmed in RAG2 deficient mice lacking adaptive immunity. Ablation of the NKp46+ NK cell compartment in RAG2 common gamma chain (gc) mice led to increased susceptibility to chronic adult B. malayi infection. This data was recapitulated using an Onchocerca ochengi male worm peritoneal implant model. When NKp46+ NK cells were depleted in RAG2 deficient mice using anti-NKp46 or asialo GM1 antibody injections over the first five weeks of B. malayi infection, susceptibility to adult B. malayi infection was significantly increased by 2-3 fold with concomitant impairment in eosinophil or neutrophil recruitments. Finally, we demonstrate that in RAG2 deficient mice, drug clearance of a primary adult B. malayi infection followed by challenge infection leads to resistance against early larval B. malayi establishment. This innate resistance is associated with bolstered NK and eosinophils whereby NKp46+ NK cells express markers of memory-like/enhanced activation (increased expression of interferon gamma and Ly6C). Our data promotes a novel functional role for NKp46+ NK cells in immunoprotection against experimental primary and secondary filarial infection which can proceed in the absence of adaptive immune regulation.
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Affiliation(s)
- Nicolas Pionnier
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Bioscience, John Dalton Building, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, United Kingdom
| | - Julio Furlong-Silva
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Stefano A P Colombo
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Amy E Marriott
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Valerine C Chunda
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Bertrand L Ndzeshang
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Hanna Sjoberg
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - John Archer
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Andrew Steven
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Samuel Wanji
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Mark J Taylor
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Joseph D Turner
- Centre for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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12
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Wiszniewsky A, Layland LE, Arndts K, Wadephul LM, Tamadaho RSE, Borrero-Wolff D, Chunda VC, Kien CA, Hoerauf A, Wanji S, Ritter M. Adoptive Transfer of Immune Cells Into RAG2IL-2Rγ-Deficient Mice During Litomosoides sigmodontis Infection: A Novel Approach to Investigate Filarial-Specific Immune Responses. Front Immunol 2021; 12:777860. [PMID: 34868049 PMCID: PMC8636703 DOI: 10.3389/fimmu.2021.777860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 10/25/2021] [Indexed: 12/03/2022] Open
Abstract
Despite long-term mass drug administration programmes, approximately 220 million people are still infected with filariae in endemic regions. Several research studies have characterized host immune responses but a major obstacle for research on human filariae has been the inability to obtain adult worms which in turn has hindered analysis on infection kinetics and immune signalling. Although the Litomosoides sigmodontis filarial mouse model is well-established, the complex immunological mechanisms associated with filarial control and disease progression remain unclear and translation to human infections is difficult, especially since human filarial infections in rodents are limited. To overcome these obstacles, we performed adoptive immune cell transfer experiments into RAG2IL-2Rγ-deficient C57BL/6 mice. These mice lack T, B and natural killer cells and are susceptible to infection with the human filaria Loa loa. In this study, we revealed a long-term release of L. sigmodontis offspring (microfilariae) in RAG2IL-2Rγ-deficient C57BL/6 mice, which contrasts to C57BL/6 mice which normally eliminate the parasites before patency. We further showed that CD4+ T cells isolated from acute L. sigmodontis-infected C57BL/6 donor mice or mice that already cleared the infection were able to eliminate the parasite and prevent inflammation at the site of infection. In addition, the clearance of the parasites was associated with Th17 polarization of the CD4+ T cells. Consequently, adoptive transfer of immune cell subsets into RAG2IL-2Rγ-deficient C57BL/6 mice will provide an optimal platform to decipher characteristics of distinct immune cells that are crucial for the immunity against rodent and human filarial infections and moreover, might be useful for preclinical research, especially about the efficacy of macrofilaricidal drugs.
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Affiliation(s)
- Anna Wiszniewsky
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Laura E Layland
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany.,German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Kathrin Arndts
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Lisa M Wadephul
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Ruth S E Tamadaho
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Dennis Borrero-Wolff
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Valerine C Chunda
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Chi Anizette Kien
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany.,German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany.,German-West African Centre for Global Health and Pandemic Prevention (G-WAC), Partner Site Bonn, Bonn, Germany
| | - Samuel Wanji
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon.,Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
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13
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Johnston KL, Hong WD, Turner JD, O'Neill PM, Ward SA, Taylor MJ. Anti-Wolbachia drugs for filariasis. Trends Parasitol 2021; 37:1068-1081. [PMID: 34229954 DOI: 10.1016/j.pt.2021.06.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/21/2021] [Accepted: 06/07/2021] [Indexed: 10/20/2022]
Abstract
The mutualistic association between Wolbachia endosymbionts and their filarial nematode hosts has been exploited as a validated drug target delivering macrofilaricidal outcomes. Limitations of existing antibiotics to scale-up have driven the search for new drugs, which are effective in shorter regimens of 7 days or less. Here, we review the last 14 years of anti-Wolbachia drug discovery by the anti-Wolbachia (A·WOL) consortium, which has screened more than two million compounds, delivering thousands of hit compounds. Refined screening models integrated with robust pharmacokinetic/pharmacodynamic (PK/PD) driven optimisation and selection strategies have delivered the first two drug candidates specifically designed to target Wolbachia. AWZ1066S and ABBV-4083 are currently progressing through clinical trials with the aim of delivering safe and effective macrofilaricides to support the elimination of onchocerciasis and lymphatic filariasis.
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Affiliation(s)
- Kelly L Johnston
- Centre for Neglected Tropical Diseases and Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK; School of Life Sciences, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - W David Hong
- Department of Chemistry, University of Liverpool, Liverpool, UK
| | - Joseph D Turner
- Centre for Neglected Tropical Diseases and Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Paul M O'Neill
- Department of Chemistry, University of Liverpool, Liverpool, UK
| | - Stephen A Ward
- Centre for Neglected Tropical Diseases and Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Mark J Taylor
- Centre for Neglected Tropical Diseases and Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
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14
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Risch F, Ritter M, Hoerauf A, Hübner MP. Human filariasis-contributions of the Litomosoides sigmodontis and Acanthocheilonema viteae animal model. Parasitol Res 2021; 120:4125-4143. [PMID: 33547508 PMCID: PMC8599372 DOI: 10.1007/s00436-020-07026-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/20/2020] [Indexed: 12/16/2022]
Abstract
Filariae are vector-borne parasitic nematodes that are endemic worldwide, in tropical and subtropical regions. Important human filariae spp. include Onchocerca volvulus, Wuchereria bancrofti and Brugia spp., and Loa loa and Mansonella spp. causing onchocerciasis (river blindness), lymphatic filariasis (lymphedema and hydrocele), loiasis (eye worm), and mansonelliasis, respectively. It is estimated that over 1 billion individuals live in endemic regions where filarial diseases are a public health concern contributing to significant disability adjusted life years (DALYs). Thus, efforts to control and eliminate filarial diseases were already launched by the WHO in the 1970s, especially against lymphatic filariasis and onchocerciasis, and are mainly based on mass drug administration (MDA) of microfilaricidal drugs (ivermectin, diethylcarbamazine, albendazole) to filarial endemic areas accompanied with vector control strategies with the goal to reduce the transmission. With the United Nations Sustainable Development Goals (SDGs), it was decided to eliminate transmission of onchocerciasis and stop lymphatic filariasis as a public health problem by 2030. It was also requested that novel drugs and treatment strategies be developed. Mouse models provide an important platform for anti-filarial drug research in a preclinical setting. This review presents an overview about the Litomosoides sigmodontis and Acanthocheilonema viteae filarial mouse models and their role in immunological research as well as preclinical studies about novel anti-filarial drugs and treatment strategies.
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Affiliation(s)
- Frederic Risch
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Marc P Hübner
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn, Bonn, Germany.
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany.
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15
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Lagatie O, Njumbe Ediage E, Van Roosbroeck D, Van Asten S, Verheyen A, Batsa Debrah L, Debrah A, Odiere MR, T’Kindt R, Dumont E, Sandra K, Dillen L, Verhaeghe T, Vreeken R, Cuyckens F, Stuyver LJ. Multimodal biomarker discovery for active Onchocerca volvulus infection. PLoS Negl Trop Dis 2021; 15:e0009999. [PMID: 34843471 PMCID: PMC8659328 DOI: 10.1371/journal.pntd.0009999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/09/2021] [Accepted: 11/16/2021] [Indexed: 11/19/2022] Open
Abstract
The neglected tropical disease onchocerciasis, or river blindness, is caused by infection with the filarial nematode Onchocerca volvulus. Current estimates indicate that 17 million people are infected worldwide, the majority of them living in Africa. Today there are no non-invasive tests available that can detect ongoing infection, and that can be used for effective monitoring of elimination programs. In addition, to enable pharmacodynamic studies with novel macrofilaricide drug candidates, surrogate endpoints and efficacy biomarkers are needed but are non-existent. We describe the use of a multimodal untargeted mass spectrometry-based approach (metabolomics and lipidomics) to identify onchocerciasis-associated metabolites in urine and plasma, and of specific lipid features in plasma of infected individuals (O. volvulus infected cases: 68 individuals with palpable nodules; lymphatic filariasis cases: 8 individuals; non-endemic controls: 20 individuals). This work resulted in the identification of elevated concentrations of the plasma metabolites inosine and hypoxanthine as biomarkers for filarial infection, and of the urine metabolite cis-cinnamoylglycine (CCG) as biomarker for O. volvulus. During the targeted validation study, metabolite-specific cutoffs were determined (inosine: 34.2 ng/ml; hypoxanthine: 1380 ng/ml; CCG: 29.7 ng/ml) and sensitivity and specificity profiles were established. Subsequent evaluation of these biomarkers in a non-endemic population from a different geographical region invalidated the urine metabolite CCG as biomarker for O. volvulus. The plasma metabolites inosine and hypoxanthine were confirmed as biomarkers for filarial infection. With the availability of targeted LC-MS procedures, the full potential of these 2 biomarkers in macrofilaricide clinical trials, MDA efficacy surveys, and epidemiological transmission studies can be investigated. Today’s diagnosis of infection with the filarial parasite Onchocerca volvulus mainly depends on the microscopic analysis of skin biopsies and serological testing. The work presented here describes the use of multiple mass spectrometry-based screening methods (metabolomics and lipidomics) to search for biomarkers indicative of infection with Onchocerca volvulus. This resulted in the identification of elevated concentrations of the plasma metabolites inosine and hypoxanthine as biomarkers for filarial infection, and of the urine metabolite cis-cinnamoylglycine as biomarker for O. volvulus. Further evaluation of these biomarkers in a geographically distinct non-endemic population however invalidated the use of urine cis-cinnamoylglycine. These findings are of utmost importance as it not only opens new avenues in the development of non-invasive diagnostic tools for filarial infections, but also emphasizes the need for evaluation and validation of newly discovered biomarkers in different populations from different geographies.
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Affiliation(s)
- Ole Lagatie
- J&J Global Public Health, Janssen R&D, Beerse, Belgium
- * E-mail:
| | | | | | | | - Ann Verheyen
- J&J Global Public Health, Janssen R&D, Beerse, Belgium
| | - Linda Batsa Debrah
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Alex Debrah
- Faculty of Allied Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Maurice R. Odiere
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - Ruben T’Kindt
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Emmie Dumont
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Koen Sandra
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Lieve Dillen
- Discovery Sciences, Janssen R&D, Beerse, Belgium
| | | | - Rob Vreeken
- Discovery Sciences, Janssen R&D, Beerse, Belgium
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16
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Wanji S, Chunda VC, Fombad FF, Jélil Njouendou A, Gandjui NVT, Ritter M, Enyong PA, Mackenzie C, Taylor MJ, Hoerauf A, Turner JD. Advances in preclinical platforms of Loa loa for filarial neglected tropical disease drug and diagnostics research. FRONTIERS IN TROPICAL DISEASES 2021; 2:778724. [PMID: 38654889 PMCID: PMC7615857 DOI: 10.3389/fitd.2021.778724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024] Open
Abstract
The tropical disease, loiasis, caused by the filarial parasite, Loa, has gained prominence in global public health as a cause of excess mortality and a barrier to the elimination of the related prioritized neglected tropical diseases (NTDs), lymphatic filariasis and onchocerciasis, within Central Africa. There are no effective drug cures or vaccines available to treat loiasis safely. Here we review recent advances in loiasis preclinical platform technologies, including novel in vitro culturing systems, animal models and innovations in experimental infections of the L. loa vector, Chrysops, that have facilitated access to all L. loa filarial life-cycle stages. We detail applications of these new model systems in anti-filarial drug screening, diagnostic development, immunology, and pathophysiology research. Finally, we provide an overview of how loiasis preclinical platforms may be further utilized in translational medicine applications to support the development of much needed new interventions against filarial NTDs.
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Affiliation(s)
- Samuel Wanji
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Valerine Chawa Chunda
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Fanny Fri Fombad
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
- Department of Zoology and Animal Physiology, Faculty of Science, University of Buea, Buea, Cameroon
| | - Abdel Jélil Njouendou
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Buea, Buea, Cameroon
| | - Narcisse Victor T. Gandjui
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Peter A. Enyong
- Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon
| | - Charles Mackenzie
- Neglected Tropical Diseases Support Center l The Task Force for Global Health, 325 Swanton Way, Decatur, Atlanta, Georgia, United States of America
| | - Mark J Taylor
- Centre for Drugs and Diagnostics Research and Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
- German Center for Infection Research (DZIF), Bonn-Cologne partner site, Bonn, Germany
| | - Joseph D Turner
- Centre for Drugs and Diagnostics Research and Centre for Neglected Tropical Diseases, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
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17
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Akumtoh DN, Njouendou AJ, Metuge HM, Sjoberg HT, Pionnier NP, Chunda VC, Gandjui NVT, Ndzeshang LB, Fombad FF, Abong RA, Enyong PA, Fru-Cho J, Esum ME, Ritter M, Taylor MJ, Turner JD, Wanji S. Onchocerca ochengi male worms implanted in SCID mice and Gerbil: Relationship between microfilaridermia status of cows, nodular worm viability and fertility and worm survival in the rodents. Exp Parasitol 2021; 229:108143. [PMID: 34437906 PMCID: PMC8518880 DOI: 10.1016/j.exppara.2021.108143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 05/06/2021] [Accepted: 08/16/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Current treatment options for onchocerciasis are sub-optimal, prompting research and development of a safe cure (macrofilaricide). Onchocerca ochengi, a parasite of cattle, is used as a close surrogate for the human parasite O. volvulus in a murine model for pre-clinical screening of macrofilaricides. Skin from naturally infected cattle have been used in previous studies as a reliable source of parasite material. However, there is limited knowledge on how source-related factors such as the microfilaridermia status of the cattle, the nodule load and nodular worm viability may affect survival of male O. ochengi worms implanted in the rodent hosts. Such relationships were investigated in this study. METHODS Dermal tissue and nodules were obtained from Gudali cattle, dissected and cultured to obtain migrating microfilariae (mf) and male worms. Emerged male worms were implanted into SCID mice and Gerbils (Meriones unguiculatus) and recovery rates were determined upon 42 days post implantation. Finally, nodules were processed for histology and embryogram analyses to assess the nodular worm viability and fertility, respectively. RESULTS Of the 69 cattle sampled, 24 (34.8%) were mf+ and 45 (65.2%) were mf-. The mean nodule loads were 180.5 ± 117.7 (mf+) and 110.6 ± 102.7 (mf-) (p = 0.0186). The mean male worm harvest from nodules were 76.8 ± 120.3 and 47.2 ± 33.4 (p = 0.2488) for mf+ and mf- cattle, respectively. The number of male worms per 100 nodules were 57/100 and 46/100 nodules for mf+ and mf- cows, respectively. Female worms from nodules of mf- cows had higher counts of both normal and abnormal embryos with higher proportions of dead nodular worms evinced by histology compared to those from mf+ cows. A total of 651 worms were implanted into mice and gerbils, out of which 129 (19.81%) were recovered. Logistic regression analysis indicated that the microfilaridermia status of the cattle (presence of mf) (OR = 4.3319; P = 0.001) is the single most important predictor of the success of male worm recovery after implantation into rodents. CONCLUSION Microfilaridermic cattle provide a promising source of adult O. ochengi. Male worms from this group of cattle have a better success rate of survival in a murine implant model. Nevertheless, in the programmatic point of view, amicrofilaridermic Gudali cattle would still constitute an important source of O. ochengi male worms with relatively good viability after implantation into rodents.
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Affiliation(s)
- Desmond N Akumtoh
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Abdel J Njouendou
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Department of Biomedical Sciences, Faculty of Health Sciences, University of Buea, Buea, Cameroon.
| | - Haelly M Metuge
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Hanna T Sjoberg
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Nicolas P Pionnier
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Valerine C Chunda
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Narcisse Victor T Gandjui
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Lontum B Ndzeshang
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Fanny F Fombad
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Department of Zoology and Animal Physiology, Faculty of Science, University of Buea, Buea, Cameroon.
| | - Raphael A Abong
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Peter A Enyong
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Jerome Fru-Cho
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Mathias E Esum
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
| | - Manuel Ritter
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany; German Center for Infection Research (DZIF), Bonn - Cologne Partner Site, Bonn, Germany.
| | - Mark J Taylor
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Joseph D Turner
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Samuel Wanji
- Research Foundation for Tropical Diseases and the Environment (REFOTDE), Buea, Cameroon; Parasite and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon.
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18
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McGillan P, Berry NG, Nixon GL, Leung SC, Webborn PJH, Wenlock MC, Kavanagh S, Cassidy A, Clare RH, Cook DA, Johnston KL, Ford L, Ward SA, Taylor MJ, Hong WD, O’Neill PM. Development of Pyrazolopyrimidine Anti- Wolbachia Agents for the Treatment of Filariasis. ACS Med Chem Lett 2021; 12:1421-1426. [PMID: 34527179 PMCID: PMC8436242 DOI: 10.1021/acsmedchemlett.1c00216] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/16/2021] [Indexed: 11/30/2022] Open
Abstract
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Anti-Wolbachia therapy has been identified as
a viable treatment for combating filarial diseases. Phenotypic screening
revealed a series of pyrazolopyrimidine hits with potent anti-Wolbachia activity. This paper focuses on the exploration
of the SAR for this chemotype, with improvement of metabolic stability
and solubility profiles using medicinal chemistry approaches. Organic
synthesis has enabled functionalization of the pyrazolopyrimidine
core at multiple positions, generating a library of compounds of which
many analogues possess nanomolar activity against Wolbachia
in vitro with improved DMPK parameters. A lead compound, 15f, was selected for in vivo pharmacokinetics
(PK) profiling in mice. The combination of potent anti-Wolbachia activity in two in vitro assessments plus the exceptional
oral PK profiles in mice puts this lead compound in a strong position
for in vivo proof-of-concept pharmacodynamics studies
and demonstrates the strong potential for further optimization and
development of this series for treatment of filariasis in the future.
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Affiliation(s)
- Paul McGillan
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Gemma L. Nixon
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Suet C. Leung
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Peter J. H. Webborn
- Drug Safety & Metabolism, IMED Biotech Unit, AstraZeneca U.K., Cambridge CB2 0AA, United Kingdom
| | - Mark C. Wenlock
- Drug Safety & Metabolism, IMED Biotech Unit, AstraZeneca U.K., Cambridge CB2 0AA, United Kingdom
| | - Stefan Kavanagh
- Oncology Safety Sciences, Clinical Pharmacology & Safety Sciences, R&D, AstraZeneca, Cambridge CB2 0AA, United Kingdom
| | - Andrew Cassidy
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Rachel H. Clare
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Darren A. Cook
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Kelly L. Johnston
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
- Institute of Systems, Molecular & Integrative Biology, School of Life Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
| | - Louise Ford
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Stephen A. Ward
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Mark J. Taylor
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - W. David Hong
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, United Kingdom
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
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19
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Furlong-Silva J, Cross SD, Marriott AE, Pionnier N, Archer J, Steven A, Merker SS, Mack M, Hong YK, Taylor MJ, Turner JD. Tetracyclines improve experimental lymphatic filariasis pathology by disrupting interleukin-4 receptor-mediated lymphangiogenesis. J Clin Invest 2021; 131:140853. [PMID: 33434186 PMCID: PMC7919730 DOI: 10.1172/jci140853] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 01/06/2021] [Indexed: 12/21/2022] Open
Abstract
Lymphatic filariasis is the major global cause of nonhereditary lymphedema. We demonstrate that the filarial nematode Brugia malayi induced lymphatic remodeling and impaired lymphatic drainage following parasitism of limb lymphatics in a mouse model. Lymphatic insufficiency was associated with elevated circulating lymphangiogenic mediators, including vascular endothelial growth factor C. Lymphatic insufficiency was dependent on type 2 adaptive immunity, the interleukin-4 receptor, and recruitment of C-C chemokine receptor-2–positive monocytes and alternatively activated macrophages with a prolymphangiogenic phenotype. Oral treatments with second-generation tetracyclines improved lymphatic function, while other classes of antibiotic had no significant effect. Second-generation tetracyclines directly targeted lymphatic endothelial cell proliferation and modified type 2 prolymphangiogenic macrophage development. Doxycycline treatment impeded monocyte recruitment, inhibited polarization of alternatively activated macrophages, and suppressed T cell adaptive immune responses following infection. Our results determine a mechanism of action for the antimorbidity effects of doxycycline in filariasis and support clinical evaluation of second-generation tetracyclines as affordable, safe therapeutics for lymphedemas of chronic inflammatory origin.
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Affiliation(s)
- Julio Furlong-Silva
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Stephen D Cross
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Amy E Marriott
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nicolas Pionnier
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - John Archer
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Andrew Steven
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Stefan Schulte Merker
- Institute for Cardiovascular Organogenesis and Regeneration, Faculty of Medicine, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Matthias Mack
- Universitätsklinikum Regensburg, Regensburg, Germany
| | - Young-Kwon Hong
- Department of Surgery, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Mark J Taylor
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Joseph D Turner
- Centre for Drugs & Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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20
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Lefoulon E, Foster JM, Truchon A, Carlow CKS, Slatko BE. The Wolbachia Symbiont: Here, There and Everywhere. Results Probl Cell Differ 2021; 69:423-451. [PMID: 33263882 DOI: 10.1007/978-3-030-51849-3_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Wolbachia symbionts, first observed in the 1920s, are now known to be present in about 30-70% of tested arthropod species, in about half of tested filarial nematodes (including the majority of human filarial nematodes), and some plant-parasitic nematodes. In arthropods, they are generally viewed as parasites while in nematodes they appear to be mutualists although this demarcation is not absolute. Their presence in arthropods generally leads to reproductive anomalies, while in nematodes, they are generally required for worm development and reproduction. In mosquitos, Wolbachia inhibit RNA viral infections, leading to populational reductions in human RNA virus pathogens, whereas in filarial nematodes, their requirement for worm fertility and survival has been channeled into their use as drug targets for filariasis control. While much more research on these ubiquitous symbionts is needed, they are viewed as playing significant roles in biological processes, ranging from arthropod speciation to human health.
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Affiliation(s)
- Emilie Lefoulon
- Molecular Parasitology Group, New England Biolabs, Inc., Ipswich, MA, USA
| | - Jeremy M Foster
- Molecular Parasitology Group, New England Biolabs, Inc., Ipswich, MA, USA
| | - Alex Truchon
- Molecular Parasitology Group, New England Biolabs, Inc., Ipswich, MA, USA
| | - C K S Carlow
- Molecular Parasitology Group, New England Biolabs, Inc., Ipswich, MA, USA
| | - Barton E Slatko
- Molecular Parasitology Group, New England Biolabs, Inc., Ipswich, MA, USA.
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21
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Loghry HJ, Yuan W, Zamanian M, Wheeler NJ, Day TA, Kimber MJ. Ivermectin inhibits extracellular vesicle secretion from parasitic nematodes. J Extracell Vesicles 2020; 10:e12036. [PMID: 33318780 PMCID: PMC7726798 DOI: 10.1002/jev2.12036] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 12/18/2022] Open
Abstract
Lymphatic filariasis (LF) is a disease caused by parasitic filarial nematodes that is endemic in 49 countries of the world and affects or threatens over 890 million people. Strategies to control LF rely heavily on mass administration of anthelmintic drugs including ivermectin (IVM), a macrocyclic lactone drug considered an Essential Medicine by the WHO. However, despite its widespread use the therapeutic mode of action of IVM against filarial nematodes is not clear. We have previously reported that filarial nematodes secrete extracellular vesicles (EVs) and that their cargo has immunomodulatory properties. Here we investigate the effects of IVM and other anti-filarial drugs on parasitic nematode EV secretion, motility, and protein secretion. We show that inhibition of EV secretion was a specific property of IVM, which had consistent and significant inhibitory effects across nematode life stages and species, with the exception of male parasites. IVM inhibited EV secretion, but not parasite motility, at therapeutically relevant concentrations. Protein secretion was inhibited by IVM in the microfilariae stage, but not in any other stage tested. Our data provides evidence that inhibiting the secretion of immunomodulatory EVs by parasitic nematodes could explain, at least in part, IVM mode of action and provides a phenotype for novel drug discovery.
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Affiliation(s)
- Hannah J. Loghry
- Department of Biomedical SciencesCollege of Veterinary MedicineIowa State UniversityAmesIowaUSA
| | - Wang Yuan
- Department of Biomedical SciencesCollege of Veterinary MedicineIowa State UniversityAmesIowaUSA
| | - Mostafa Zamanian
- Department of Pathobiological SciencesUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Nicolas J. Wheeler
- Department of Pathobiological SciencesUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Timothy A. Day
- Department of Biomedical SciencesCollege of Veterinary MedicineIowa State UniversityAmesIowaUSA
| | - Michael J. Kimber
- Department of Biomedical SciencesCollege of Veterinary MedicineIowa State UniversityAmesIowaUSA
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22
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Oxfendazole mediates macrofilaricidal efficacy against the filarial nematode Litomosoides sigmodontis in vivo and inhibits Onchocerca spec. motility in vitro. PLoS Negl Trop Dis 2020; 14:e0008427. [PMID: 32628671 PMCID: PMC7365463 DOI: 10.1371/journal.pntd.0008427] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 07/16/2020] [Accepted: 05/27/2020] [Indexed: 12/13/2022] Open
Abstract
A major impediment to eliminate lymphatic filariasis and onchocerciasis is the lack of effective short-course macrofilaricidal drugs or regimens that are proven to be safe for both infections. In this study we tested oxfendazole, an anthelmintic shown to be well tolerated in phase 1 clinical trials. In vitro, oxfendazole exhibited modest to marginal motility inhibition of adult worms of Onchocerca gutturosa, pre-adult worms of Onchocerca volvulus and Onchocerca lienalis microfilariae. In vivo, five days of oral treatments provided sterile cure with up to 100% macrofilaricidal efficacy in the murine Litomosoides sigmodontis model of filariasis. In addition, 10 days of oral treatments with oxfendazole inhibited filarial embryogenesis in patent L. sigmodontis-infected jirds and subsequently led to a protracted but complete clearance of microfilaremia. The macrofilaricidal effect observed in vivo was selective, as treatment with oxfendazole of microfilariae-injected naïve mice was ineffective. Based on pharmacokinetic analysis, the driver of efficacy is the maintenance of a minimal efficacious concentration of approximately 100 ng/ml (based on subcutaneous treatment at 25 mg/kg in mice). From animal models, the human efficacious dose is predicted to range from 1.5 to 4.1 mg/kg. Such a dose has already been proven to be safe in phase 1 clinical trials. Oxfendazole therefore has potential to be efficacious for treatment of human filariasis without causing adverse reactions due to drug-induced microfilariae killing. Onchocerciasis and lymphatic filariasis represent two debilitating filarial diseases that belong to the neglected tropical diseases. The current efforts to eliminate those diseases is hampered by the lack of short-course macrofilaricidal drugs, i.e. drugs that kill the adult worms, or regimens that are proven to be safe for both diseases. In the present study we demonstrate that the anthelmintic drug oxfendazole, currently used in veterinary medicine against intestinal helminths, has excellent efficacy in the Litomosoides sigmodontis rodent model of filariasis. Oxfendazole caused complete clearance of adult filariae after a short oral regimen in vivo. Oxfendazole was not directly active against the circulating filarial progeny, the microfilariae, suggesting that drug-induced serious adverse events due to the clearance of microfilariae are unlikely. Human dose was predicted based on the efficacy in the rodent model, the calculation estimated a low efficacious dose, which has already been shown to be safe in phase 1 clinical trials. Thus, oxfendazole represents a promising drug candidate for the treatment of human filarial diseases such as onchocerciasis and lymphatic filariasis.
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23
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Gunderson EL, Vogel I, Chappell L, Bulman CA, Lim KC, Luo M, Whitman JD, Franklin C, Choi YJ, Lefoulon E, Clark T, Beerntsen B, Slatko B, Mitreva M, Sullivan W, Sakanari JA. The endosymbiont Wolbachia rebounds following antibiotic treatment. PLoS Pathog 2020; 16:e1008623. [PMID: 32639986 PMCID: PMC7371230 DOI: 10.1371/journal.ppat.1008623] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 07/20/2020] [Accepted: 05/13/2020] [Indexed: 12/20/2022] Open
Abstract
Antibiotic treatment has emerged as a promising strategy to sterilize and kill filarial nematodes due to their dependence on their endosymbiotic bacteria, Wolbachia. Several studies have shown that novel and FDA-approved antibiotics are efficacious at depleting the filarial nematodes of their endosymbiont, thus reducing female fecundity. However, it remains unclear if antibiotics can permanently deplete Wolbachia and cause sterility for the lifespan of the adult worms. Concerns about resistance arising from mass drug administration necessitate a careful exploration of potential Wolbachia recrudescence. In the present study, we investigated the long-term effects of the FDA-approved antibiotic, rifampicin, in the Brugia pahangi jird model of infection. Initially, rifampicin treatment depleted Wolbachia in adult worms and simultaneously impaired female worm fecundity. However, during an 8-month washout period, Wolbachia titers rebounded and embryogenesis returned to normal. Genome sequence analyses of Wolbachia revealed that despite the population bottleneck and recovery, no genetic changes occurred that could account for the rebound. Clusters of densely packed Wolbachia within the worm's ovarian tissues were observed by confocal microscopy and remained in worms treated with rifampicin, suggesting that they may serve as privileged sites that allow Wolbachia to persist in worms while treated with antibiotic. To our knowledge, these clusters have not been previously described and may be the source of the Wolbachia rebound.
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Affiliation(s)
- Emma L. Gunderson
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - Ian Vogel
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - Laura Chappell
- Dept. of Molecular, Cell and Developmental Biology; University of California, Santa Cruz; Santa Cruz, California, United States of America
| | - Christina A. Bulman
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - K. C. Lim
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - Mona Luo
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - Jeffrey D. Whitman
- Dept. of Laboratory Medicine; University of California, San Francisco; San Francisco, California, United States of America
| | - Chris Franklin
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
| | - Young-Jun Choi
- Division of Infectious Diseases; Washington University School of Medicine, St. Louis; St. Louis, Missouri, United States of America
| | - Emilie Lefoulon
- Molecular Parasitology Division; New England BioLabs; Ipswich, Massachusetts, United States of America
| | - Travis Clark
- Veterinary Pathobiology; University of Missouri-Columbia; Columbia, Missouri, United States of America
| | - Brenda Beerntsen
- Veterinary Pathobiology; University of Missouri-Columbia; Columbia, Missouri, United States of America
| | - Barton Slatko
- Molecular Parasitology Division; New England BioLabs; Ipswich, Massachusetts, United States of America
| | - Makedonka Mitreva
- Division of Infectious Diseases; Washington University School of Medicine, St. Louis; St. Louis, Missouri, United States of America
| | - William Sullivan
- Dept. of Molecular, Cell and Developmental Biology; University of California, Santa Cruz; Santa Cruz, California, United States of America
| | - Judy A. Sakanari
- Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America
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24
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Pionnier N, Sjoberg H, Furlong-Silva J, Marriott A, Halliday A, Archer J, Steven A, Taylor MJ, Turner JD. Eosinophil-Mediated Immune Control of Adult Filarial Nematode Infection Can Proceed in the Absence of IL-4 Receptor Signaling. THE JOURNAL OF IMMUNOLOGY 2020; 205:731-740. [PMID: 32571840 PMCID: PMC7372315 DOI: 10.4049/jimmunol.1901244] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 05/17/2020] [Indexed: 12/19/2022]
Abstract
Immunity to chronic filarial worm infection is apparent in IL-4Rα–deficient mice. Delayed immunity in IL-4Rα−/− mice is due to suboptimal tissue eosinophilia. Eosinophil recruitment in the absence of IL-4R signaling requires CCR3 and IL-5.
Helminth infections are accompanied by eosinophilia in parasitized tissues. Eosinophils are effectors of immunity to tissue helminths. We previously reported that in the context of experimental filarial nematode infection, optimum tissue eosinophil recruitment was coordinated by local macrophage populations following IL-4R–dependent in situ proliferation and alternative activation. However, in the current study, we identify that control of chronic adult filarial worm infection is evident in IL-4Rα–deficient (IL-4Rα−/−) mice, whereby the majority of infections do not achieve patency. An associated residual eosinophilia was apparent in infected IL-4Rα−/− mice. By treating IL-4Rα−/− mice serially with anti-CCR3 Ab or introducing a compound deficiency in CCR3 within IL-4Rα−/− mice, residual eosinophilia was ablated, and susceptibility to chronic adult Brugia malayi infection was established, promoting a functional role for CCR3-dependent eosinophil influx in immune control in the absence of IL-4/IL-13–dependent immune mechanisms. We investigated additional cytokine signals involved in residual eosinophilia in the absence IL-4Rα signaling and defined that IL-4Rα−/−/IL-5−/− double-knockout mice displayed significant eosinophil deficiency compared with IL-4Rα−/− mice and were susceptible to chronic fecund adult filarial infections. Contrastingly, there was no evidence that either IL-4R–dependent or IL-4R–independent/CCR3/IL-5–dependent immunity influenced B. malayi microfilarial loads in the blood. Our data demonstrate multiplicity of Th2-cytokine control of eosinophil tissue recruitment during chronic filarial infection and that IL-4R–independent/IL-5– and CCR3-dependent pathways are sufficient to control filarial adult infection via an eosinophil-dependent effector response prior to patency.
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Affiliation(s)
- Nicolas Pionnier
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Hanna Sjoberg
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Julio Furlong-Silva
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Amy Marriott
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Alice Halliday
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - John Archer
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Andrew Steven
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Mark J Taylor
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Joseph D Turner
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
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25
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Pilotte N, Cook DA, Pryce J, Zulch MF, Minetti C, Reimer LJ, Williams SA. Laboratory evaluation of molecular xenomonitoring using mosquito and tsetse fly excreta/feces to amplify Plasmodium, Brugia, and Trypanosoma DNA. Gates Open Res 2020; 3:1734. [PMID: 32596646 PMCID: PMC7308644 DOI: 10.12688/gatesopenres.13093.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2020] [Indexed: 11/20/2022] Open
Abstract
Background: Results from an increasing number of studies suggest that mosquito excreta/feces (E/F) testing has considerable potential to serve as a supplement for traditional molecular xenomonitoring techniques. However, as the catalogue of possible use-cases for this methodology expands, and the list of amenable pathogens grows, a number of fundamental methods-based questions remain. Answering these questions is critical to maximizing the utility of this approach and to facilitating its successful implementation as an effective tool for molecular xenomonitoring. Methods: Utilizing E/F produced by mosquitoes or tsetse flies experimentally exposed to Brugia malayi, Plasmodium falciparum, or Trypanosoma brucei brucei, factors such as limits of detection, throughput of testing, adaptability to use with competent and incompetent vector species, and effects of additional blood feedings post parasite-exposure were evaluated. Two platforms for the detection of pathogen signal (quantitative real-time PCR and digital PCR (dPCR)) were also compared, with strengths and weaknesses examined for each. Results: Experimental results indicated that high throughput testing is possible when evaluating mosquito E/F for the presence of either B. malayi or P. falciparum from both competent and incompetent vector mosquito species. Furthermore, following exposure to pathogen, providing mosquitoes with a second, uninfected bloodmeal did not expand the temporal window for E/F collection during which pathogen detection was possible. However, this collection window did appear longer in E/F collected from tsetse flies following exposure to T. b. brucei. Testing also suggested that dPCR may facilitate detection through its increased sensitivity. Unfortunately, logistical obstacles will likely make the large-scale use of dPCR impractical for this purpose. Conclusions: By examining many E/F testing variables, expansion of this technology to a field-ready platform has become increasingly feasible. However, translation of this methodology from the lab to the field will first require field-based pilot studies aimed at assessing the efficacy of E/F screening.
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Affiliation(s)
- Nils Pilotte
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts, 01003, USA
| | - Darren A.N. Cook
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Joseph Pryce
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Michael F. Zulch
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
| | - Corrado Minetti
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Lisa J. Reimer
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Steven A. Williams
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts, 01003, USA
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26
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Taylor MJ, von Geldern TW, Ford L, Hübner MP, Marsh K, Johnston KL, Sjoberg HT, Specht S, Pionnier N, Tyrer HE, Clare RH, Cook DAN, Murphy E, Steven A, Archer J, Bloemker D, Lenz F, Koschel M, Ehrens A, Metuge HM, Chunda VC, Ndongmo Chounna PW, Njouendou AJ, Fombad FF, Carr R, Morton HE, Aljayyoussi G, Hoerauf A, Wanji S, Kempf DJ, Turner JD, Ward SA. Preclinical development of an oral anti- Wolbachia macrolide drug for the treatment of lymphatic filariasis and onchocerciasis. Sci Transl Med 2020; 11:11/483/eaau2086. [PMID: 30867321 DOI: 10.1126/scitranslmed.aau2086] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 10/19/2018] [Indexed: 01/04/2023]
Abstract
There is an urgent global need for a safe macrofilaricide drug to accelerate elimination of the neglected tropical diseases onchocerciasis and lymphatic filariasis. From an anti-infective compound library, the macrolide veterinary antibiotic, tylosin A, was identified as a hit against Wolbachia This bacterial endosymbiont is required for filarial worm viability and fertility and is a validated target for macrofilaricidal drugs. Medicinal chemistry was undertaken to develop tylosin A analogs with improved oral bioavailability. Two analogs, A-1535469 and A-1574083, were selected. Their efficacy was tested against the gold-standard second-generation tetracycline antibiotics, doxycycline and minocycline, in mouse and gerbil infection models of lymphatic filariasis (Brugia malayi and Litomosoides sigmodontis) and onchocerciasis (Onchocerca ochengi). A 1- or 2-week course of oral A-1535469 or A-1574083 provided >90% Wolbachia depletion from nematodes in infected animals, resulting in a block in embryogenesis and depletion of microfilarial worm loads. The two analogs delivered comparative or superior efficacy compared to a 3- to 4-week course of doxycycline or minocycline. A-1574083 (now called ABBV-4083) was selected for further preclinical testing. Cardiovascular studies in dogs and toxicology studies in rats and dogs revealed no adverse effects at doses (50 mg/kg) that achieved plasma concentrations >10-fold above the efficacious concentration. A-1574083 (ABBV-4083) shows potential as an anti-Wolbachia macrolide with an efficacy, pharmacology, and safety profile that is compatible with a short-term oral drug course for treating lymphatic filariasis and onchocerciasis.
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Affiliation(s)
- Mark J Taylor
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Thomas W von Geldern
- Global Pharmaceutical Research and Development, AbbVie, North Chicago, IL, USA.,Franciscan Institute for World Health, Franciscan University, Steubenville, OH, USA
| | - Louise Ford
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Marc P Hübner
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Kennan Marsh
- Global Pharmaceutical Research and Development, AbbVie, North Chicago, IL, USA
| | - Kelly L Johnston
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Hanna T Sjoberg
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Sabine Specht
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Nicolas Pionnier
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Hayley E Tyrer
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Rachel H Clare
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Darren A N Cook
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Emma Murphy
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Andrew Steven
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - John Archer
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Dominique Bloemker
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Franziska Lenz
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Marianne Koschel
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Alexandra Ehrens
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Haelly M Metuge
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Valerinne C Chunda
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Patrick W Ndongmo Chounna
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Abdel J Njouendou
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Fanny F Fombad
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Robert Carr
- Global Pharmaceutical Research and Development, AbbVie, North Chicago, IL, USA
| | - Howard E Morton
- Global Pharmaceutical Research and Development, AbbVie, North Chicago, IL, USA
| | - Ghaith Aljayyoussi
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Samuel Wanji
- Research Foundation for Tropical Diseases and the Environment, Buea, Cameroon.,Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Dale J Kempf
- Global Pharmaceutical Research and Development, AbbVie, North Chicago, IL, USA
| | - Joseph D Turner
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Stephen A Ward
- Centre for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK.
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27
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Chunda VC, Ritter M, Bate A, Gandjui NVT, Esum ME, Fombad FF, Njouendou AJ, Ndongmo PWC, Taylor MJ, Hoerauf A, Layland LE, Turner JD, Wanji S. Comparison of immune responses to Loa loa stage-specific antigen extracts in Loa loa-exposed BALB/c mice upon clearance of infection. Parasit Vectors 2020; 13:51. [PMID: 32033624 PMCID: PMC7006431 DOI: 10.1186/s13071-020-3921-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 01/31/2020] [Indexed: 01/10/2023] Open
Abstract
Background Different immune mechanisms are capable of killing developmental stages of filarial nematodes and these mechanisms are also likely to vary between the primary and a challenge infection. However, the lack of a detailed analysis of cytokine, chemokine and immunoglobulin levels in human loiasis is still evident. Therefore, detailed analysis of immune responses induced by the different developmental stages of Loa loa in immune-competent BALB/c mice will aid in the characterization of distinct immune responses that are important for the immunity against loiasis. Methods Different developmental stages of L. loa were obtained from human peripheral blood (microfilariae, MF), the transmitting vector, Chrysops (larval stage 3, L3) and infected immune-deficient BALB/cRAG2γc−/− mice (L4, L5, adult worms). Groups of wildtype BALB/c mice were then injected with the isolated stages and after 42 days post-infection (pi), systemic cytokine, chemokine and immunoglobulin levels were determined. These were then compared to L. loa-specific responses from in vitro re-stimulated splenocytes from individual mice. All parameters were determined using Luminex technology. Results In a pilot study, BALB/c mice cleared the different life stages of L. loa within 42 days pi and systemic cytokine, chemokine and immunoglobulin levels were equal between infected and naive mice. Nevertheless, L. loa-specific re-stimulation of splenocytes from mice infected with L5, MF or adult worms led to induction of Th2, Th17 and chemokine secretion patterns. Conclusions This study shows that although host immunity remains comparable to naive mice, clearance of L. loa life-cycle development stages can induce immune cell memory leading to cytokine, chemokine and immunoglobulins secretion patterns which might contribute to immunity and protection against reinfection.![]()
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Affiliation(s)
- Valerine C Chunda
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Manuel Ritter
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), Medical Faculty, University of Bonn, Bonn, Germany.
| | - Ayukenchengamba Bate
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Narcisse V T Gandjui
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Mathias E Esum
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Fanny F Fombad
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Abdel J Njouendou
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Patrick W C Ndongmo
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
| | - Mark J Taylor
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), Medical Faculty, University of Bonn, Bonn, Germany.,German Centre for Infection Research (DZIF), Bonn-Cologne partner site, Bonn, Germany
| | - Laura E Layland
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), Medical Faculty, University of Bonn, Bonn, Germany.,German Centre for Infection Research (DZIF), Bonn-Cologne partner site, Bonn, Germany
| | - Joseph D Turner
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Samuel Wanji
- Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon
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Pilotte N, Cook DA, Pryce J, Zulch MF, Minetti C, Reimer LJ, Williams SA. Laboratory evaluation of molecular xenomonitoring using mosquito excreta/feces to amplify Plasmodium, Brugia, and Trypanosoma DNA. Gates Open Res 2019; 3:1734. [PMID: 32596646 PMCID: PMC7308644 DOI: 10.12688/gatesopenres.13093.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2019] [Indexed: 03/30/2024] Open
Abstract
Background: Results from an increasing number of studies suggest that mosquito excreta/feces (E/F) testing has considerable potential to serve as a supplement for traditional molecular xenomonitoring techniques. However, as the catalogue of possible use-cases for this methodology expands, and the list of amenable pathogens grows, a number of fundamental methods-based questions remain. Answering these questions is critical to maximizing the utility of this approach and to facilitating its successful implementation as an effective tool for molecular xenomonitoring. Methods: Utilizing E/F produced by mosquitoes or tsetse flies experimentally exposed to Brugia malayi, Plasmodium falciparum, or Trypanosoma brucei brucei, factors such as limits of detection, throughput of testing, adaptability to use with competent- and incompetent-vector species, and effects of additional blood feedings post parasite-exposure were evaluated. Two platforms for the detection of pathogen signal (quantitative real-time PCR and digital PCR [dPCR]) were also compared, with strengths and weaknesses examined for each. Results: Experimental results indicated that high throughput testing is possible when evaluating mosquito E/F for the presence of either B. malayi or P. falciparum from both competent- and incompetent-vector mosquito species. Furthermore, following exposure to pathogen, providing mosquitoes with a second, uninfected bloodmeal did not expand the temporal window for E/F collection during which pathogen detection was possible. However, this collection window did appear longer in E/F collected from tsetse flies following exposure to T. b. brucei. Testing also suggested that dPCR may facilitate detection through its increased sensitivity. Unfortunately, logistical obstacles will likely make the large-scale use of dPCR impractical for this purpose. Conclusions: By examining many E/F testing variables, expansion of this technology to a field-ready platform has become increasingly feasible. However, translation of this methodology from the lab to the field will first require the completion of field-based pilot studies aimed at assessing the efficacy of E/F screening.
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Affiliation(s)
- Nils Pilotte
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts, 01003, USA
| | - Darren A.N. Cook
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Joseph Pryce
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Michael F. Zulch
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
| | - Corrado Minetti
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Lisa J. Reimer
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Steven A. Williams
- Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01063, USA
- Molecular and Cellular Biology Program, University of Massachusetts, Amherst, Massachusetts, 01003, USA
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29
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Short-course quinazoline drug treatments are effective in the Litomosoides sigmodontis and Brugia pahangi jird models. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2019; 12:18-27. [PMID: 31869759 PMCID: PMC6931063 DOI: 10.1016/j.ijpddr.2019.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/30/2019] [Accepted: 12/02/2019] [Indexed: 12/26/2022]
Abstract
The quinazolines CBR417 and CBR490 were previously shown to be potent anti-wolbachials that deplete Wolbachia endosymbionts of filarial nematodes and present promising pre-clinical candidates for human filarial diseases such as onchocerciasis. In the present study we tested both candidates in two models of chronic filarial infection, namely the Litomosoides sigmodontis and Brugia pahangi jird model and assessed their long-term effect on Wolbachia depletion, microfilariae counts and filarial embryogenesis 16−18 weeks after treatment initiation (wpt). Once per day (QD) oral treatment with CBR417 (50 mg/kg) for 4 days or twice per day (BID) with CBR490 (25 mg/kg) for 7 days during patent L. sigmodontis infection reduced the Wolbachia load by >99% and completely cleared peripheral microfilaremia from 10–14 wpt. Similarly, 7 days of QD treatments (40 mg/kg) with CBR417 or CBR490 cleared >99% of Wolbachia from B. pahangi and reduced peritoneal microfilariae counts by 93% in the case of CBR417 treatment. Transmission electron microscopy analysis indicated intensive damage to the B. pahangi ovaries following CBR417 treatment and in accordance filarial embryogenesis was inhibited in both models after CBR417 or CBR490 treatment. Suboptimal treatment regimens of CBR417 or CBR490 did not lead to a maintained reduction of the microfilariae and Wolbachia load. In conclusion, CBR417 or CBR490 are pre-clinical candidates for filarial diseases, which achieve long-term clearance of Wolbachia endosymbionts of filarial nematodes, inhibit filarial embryogenesis and clear microfilaremia with treatments as short as 7 days. CBR417 and CBR490 provide long-term effects in 2 chronic filaria jird models. CBR417 and CBR490 deplete >99% Wolbachia in B. pahangi and L. sigmodontis filariae. CBR417 and CBR490 clear L. sigmodontis microfilariae after 10–14 weeks. CBR417 and CBR490 inhibit filarial embryogenesis in both models. Suboptimal doses do not maintain reduction of microfilariae and Wolbachia.
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30
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Wanji S, Nji TM, Hamill L, Dean L, Ozano K, Njouendou AJ, Abong RA, Obie ED, Amuam A, Ekanya R, Ndongmo WPC, Ndzeshang BL, Fung EG, Nnamdi DB, Nkimbeng DA, Teghen S, Kah E, Piotrowski H, Forrer A, Khan JAM, Woode ME, Niessen L, Watson V, Njoumemi Z, Murdoch ME, Thomson R, Theobald S, Enyong P, Turner JD, Taylor MJ. Implementation of test-and-treat with doxycycline and temephos ground larviciding as alternative strategies for accelerating onchocerciasis elimination in an area of loiasis co-endemicity: the COUNTDOWN consortium multi-disciplinary study protocol. Parasit Vectors 2019; 12:574. [PMID: 31801631 PMCID: PMC6894124 DOI: 10.1186/s13071-019-3826-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 11/25/2019] [Indexed: 12/15/2022] Open
Abstract
Background Onchocerciasis is a priority neglected tropical disease targeted for elimination by 2025. The standard strategy to combat onchocerciasis is annual Community-Directed Treatment with ivermectin (CDTi). Yet, high prevalence rates and transmission persist following > 12 rounds in South-West Cameroon. Challenges include programme coverage, adherence to, and acceptability of ivermectin in an area of Loa loa co-endemicity. Loiasis patients harbouring heavy infections are at risk of potentially fatal serious adverse events following CDTi. Alternative strategies are therefore needed to achieve onchocerciasis elimination where CDTi effectiveness is suboptimal. Methods/design We designed an implementation study to evaluate integrating World Health Organisation-endorsed alternative strategies for the elimination of onchocerciasis, namely test-and-treat with the macrofilaricide, doxycycline (TTd), and ground larviciding for suppression of blackfly vectors with the organophosphate temephos. A community-based controlled before-after intervention study will be conducted among > 2000 participants in 20 intervention (Meme River Basin) and 10 control (Indian River Basin) communities. The primary outcome measure is O. volvulus prevalence at follow-up 18-months post-treatment. The study involves four inter-disciplinary components: parasitology, entomology, applied social sciences and health economics. Onchocerciasis skin infection will be diagnosed by skin biopsy and Loa loa infection will be diagnosed by parasitological examination of finger-prick blood samples. A simultaneous clinical skin disease assessment will be made. Eligible skin-snip-positive individuals will be offered directly-observed treatment for 5 weeks with 100 mg/day doxycycline. Transmission assessments of onchocerciasis in the communities will be collected post-human landing catch of the local biting blackfly vector prior to ground larviciding with temephos every week (0.3 l/m3) until biting rate falls below 5/person/day. Qualitative research, including in-depth interviews and focus-group discussions will be used to assess acceptability and feasibility of the implemented alternative strategies among intervention recipients and providers. Health economics will assess the cost-effectiveness of the implemented interventions. Conclusions Using a multidisciplinary approach, we aim to assess the effectiveness of TTd, alone or in combination with ground larviciding, following a single intervention round and scrutinise the acceptability and feasibility of implementing at scale in similar hotspots of onchocerciasis infection, to accelerate onchocerciasis elimination.
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Affiliation(s)
- Samuel Wanji
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon. .,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.
| | - Theobald Mue Nji
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | | | - Laura Dean
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Kim Ozano
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Abdel J Njouendou
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Biomedical Sciences, Faculty of Health Sciences, University of Buea, P.O. Box 12, Buea, Cameroon
| | - Raphael A Abong
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Elisabeth Dibando Obie
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Andrew Amuam
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Relindis Ekanya
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Winston Patrick Chounna Ndongmo
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Bertrand L Ndzeshang
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Ebua Gallus Fung
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Dum-Buo Nnamdi
- COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon.,COUNTDOWN, Department of Sociology and Anthropology, Faculty of Social and Management Sciences, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Desmond Akumtoh Nkimbeng
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Samuel Teghen
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Emmanuel Kah
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Helen Piotrowski
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Armelle Forrer
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Jahangir A M Khan
- COUNTDOWN, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Maame E Woode
- Centre for Health Economics, Monash University, Victoria, Australia
| | - Louis Niessen
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.,Department of International Health, Johns Hopkins School of Public Health, Baltimore, USA
| | - Victoria Watson
- COUNTDOWN, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Zakariaou Njoumemi
- Health Economics Unit, Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaounde I, P.O. Box 1364, Yaounde, Cameroon
| | - Michele E Murdoch
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.,West Herts Hospitals NHS Trust, Watford General Hospital, Vicarage Road, Watford, UK
| | - Rachael Thomson
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Sally Theobald
- COUNTDOWN, Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Peter Enyong
- COUNTDOWN, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon.,COUNTDOWN, Research Foundation for Tropical Diseases and Environment, P.O. Box 474, Buea, Cameroon
| | - Joseph D Turner
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK.
| | - Mark J Taylor
- COUNTDOWN, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
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Bakowski MA, McNamara CW. Advances in Antiwolbachial Drug Discovery for Treatment of Parasitic Filarial Worm Infections. Trop Med Infect Dis 2019; 4:tropicalmed4030108. [PMID: 31323841 PMCID: PMC6789823 DOI: 10.3390/tropicalmed4030108] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 01/09/2023] Open
Abstract
The intracellular bacteria now known as Wolbachia were first described in filarial worms in the 1970s, but the idea of Wolbachia being used as a macrofilaricidal target did not gain wide attention until the early 2000s, with research in filariae suggesting the requirement of worms for the endosymbiont. This new-found interest prompted the eventual organization of the Anti-Wolbachia Consortium (A-WOL) at the Liverpool School of Tropical Medicine, who, among others have been active in the field of antiwolbachial drug discovery to treat filarial infections. Clinical proof of concept studies using doxycycline demonstrated the utility of the antiwolbachial therapy, but efficacious treatments were of long duration and not safe for all infected. With the advance of robotics, automation, and high-speed computing, the search for superior antiwolbachials shifted away from smaller studies with a select number of antibiotics to high-throughput screening approaches, centered largely around cell-based phenotypic screens due to the rather limited knowledge about, and tools available to manipulate, this bacterium. A concomitant effort was put towards developing validation approaches and in vivo models supporting drug discovery efforts. In this review, we summarize the strategies behind and outcomes of recent large phenotypic screens published within the last 5 years, hit compound validation approaches and promising candidates with profiles superior to doxycycline, including ones positioned to advance into clinical trials for treatment of filarial worm infections.
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Cho-Ngwa F, Mbah GE, Ayiseh RB, Ndi EM, Monya E, Tumanjong IM, Mainsah EN, Sakanari J, Lustigman S. Development and validation of an Onchocerca ochengi adult male worm gerbil model for macrofilaricidal drug screening. PLoS Negl Trop Dis 2019; 13:e0007556. [PMID: 31260456 PMCID: PMC6625737 DOI: 10.1371/journal.pntd.0007556] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 07/12/2019] [Accepted: 06/18/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Onchocerciasis currently afflicts an estimated 15 million people and is the second leading infectious cause of blindness world-wide. The development of a macrofilaricide to cure the disease has been hindered by the lack of appropriate small laboratory animal models. This study therefore, was aimed at developing and validating the Mongolian gerbil, as an Onchocerca ochengi (the closest in phylogeny to O. volvulus) adult male worm model. METHODOLOGY/PRINCIPAL FINDINGS Mongolian gerbils (Meriones unguiculatus) were each implanted with 20 O. ochengi male worms (collected from infected cattle), in the peritoneum. Following drug or placebo treatments, the implanted worms were recovered from the animals and analyzed for burden, motility and viability. Worm recovery in control gerbils was on average 35%, with 89% of the worms being 100% motile. Treatment of the gerbils implanted with male worms with flubendazole (FBZ) resulted in a significant reduction (p = 0.0021) in worm burden (6.0% versus 27.8% in the control animals); all recovered worms from the treated group had 0% worm motility versus 91.1% motility in control animals. FBZ treatment had similar results even after four different experiments. Using this model, we tested a related drug, oxfendazole (OFZ), and found it to also significantly (p = 0.0097) affect worm motility (22.7% versus 95.0% in the control group). CONCLUSIONS/SIGNIFICANCE We have developed and validated a novel gerbil O. ochengi adult male worm model for testing new macrofilaricidal drugs in vivo. It was also used to determine the efficacy of oxfendazole in vivo.
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Affiliation(s)
- Fidelis Cho-Ngwa
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Glory Enjong Mbah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Rene Bilingwe Ayiseh
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Emmanuel Menang Ndi
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Elvis Monya
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Irene Memeh Tumanjong
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Evans Ngandung Mainsah
- ANDI Centre of Excellence for Onchocerciasis Drug Research, Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, United States of America
| | - Sara Lustigman
- Lindsley F. Kimball Research Institute, New York City, New York, United States of America
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33
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Bakowski MA, Shiroodi RK, Liu R, Olejniczak J, Yang B, Gagaring K, Guo H, White PM, Chappell L, Debec A, Landmann F, Dubben B, Lenz F, Struever D, Ehrens A, Frohberger SJ, Sjoberg H, Pionnier N, Murphy E, Archer J, Steven A, Chunda VC, Fombad FF, Chounna PW, Njouendou AJ, Metuge HM, Ndzeshang BL, Gandjui NV, Akumtoh DN, Kwenti TDB, Woods AK, Joseph SB, Hull MV, Xiong W, Kuhen KL, Taylor MJ, Wanji S, Turner JD, Hübner MP, Hoerauf A, Chatterjee AK, Roland J, Tremblay MS, Schultz PG, Sullivan W, Chu XJ, Petrassi HM, McNamara CW. Discovery of short-course antiwolbachial quinazolines for elimination of filarial worm infections. Sci Transl Med 2019; 11:11/491/eaav3523. [DOI: 10.1126/scitranslmed.aav3523] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 03/18/2019] [Indexed: 12/21/2022]
Abstract
Parasitic filarial nematodes cause debilitating infections in people in resource-limited countries. A clinically validated approach to eliminating worms uses a 4- to 6-week course of doxycycline that targetsWolbachia, a bacterial endosymbiont required for worm viability and reproduction. However, the prolonged length of therapy and contraindication in children and pregnant women have slowed adoption of this treatment. Here, we describe discovery and optimization of quinazolines CBR417 and CBR490 that, with a single dose, achieve >99% elimination ofWolbachiain the in vivoLitomosoides sigmodontisfilarial infection model. The efficacious quinazoline series was identified by pairing a primary cell-based high-content imaging screen with an orthogonal ex vivo validation assay to rapidly quantifyWolbachiaelimination inBrugia pahangifilarial ovaries. We screened 300,368 small molecules in the primary assay and identified 288 potent and selective hits. Of 134 primary hits tested, only 23.9% were active in the worm-based validation assay, 8 of which contained a quinazoline heterocycle core. Medicinal chemistry optimization generated quinazolines with excellent pharmacokinetic profiles in mice. Potent antiwolbachial activity was confirmed inL. sigmodontis,Brugia malayi, andOnchocerca ochengiin vivo preclinical models of filarial disease and in vitro selectivity againstLoa loa(a safety concern in endemic areas). The favorable efficacy and in vitro safety profiles of CBR490 and CBR417 further support these as clinical candidates for treatment of filarial infections.
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Pionnier NP, Sjoberg H, Chunda VC, Fombad FF, Chounna PW, Njouendou AJ, Metuge HM, Ndzeshang BL, Gandjui NV, Akumtoh DN, Tayong DB, Taylor MJ, Wanji S, Turner JD. Mouse models of Loa loa. Nat Commun 2019; 10:1429. [PMID: 30926803 PMCID: PMC6441053 DOI: 10.1038/s41467-019-09442-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 03/07/2019] [Indexed: 12/14/2022] Open
Abstract
Elimination of the helminth disease, river blindness, remains challenging due to ivermectin treatment-associated adverse reactions in loiasis co-infected patients. Here, we address a deficit in preclinical research tools for filarial translational research by developing Loa loa mouse infection models. We demonstrate that adult Loa loa worms in subcutaneous tissues, circulating microfilariae (mf) and presence of filarial biomarkers in sera occur following experimental infections of lymphopenic mice deficient in interleukin (IL)-2/7 gamma-chain signaling. A microfilaraemic infection model is also achievable, utilizing immune-competent or -deficient mice infused with purified Loa mf. Ivermectin but not benzimidazole treatments induce rapid decline (>90%) in parasitaemias in microfilaraemic mice. We identify up-regulation of inflammatory markers associated with allergic type-2 immune responses and eosinophilia post-ivermectin treatment. Thus, we provide validation of murine research models to identify loiasis biomarkers, to counter-screen candidate river blindness cures and to interrogate the inflammatory etiology of loiasis ivermectin-associated adverse reactions. Here, the authors develop a mouse model of Loa loa that reflects human infections, including eosinophilia, and determine effects of ivermectin treatment.
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Affiliation(s)
- Nicolas P Pionnier
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Hanna Sjoberg
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Valerine C Chunda
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Fanny F Fombad
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Patrick W Chounna
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Abdel J Njouendou
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Haelly M Metuge
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Bertrand L Ndzeshang
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Narcisse V Gandjui
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Desmond N Akumtoh
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Dizzle B Tayong
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Mark J Taylor
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Samuel Wanji
- Research Foundation in Tropical Diseases and the Environment, P.O. Box 474, Buea, Cameroon.,Parasite and Vector Biology Research Unit, Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Cameroon
| | - Joseph D Turner
- Centre for Drugs and Diagnostics Research, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
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35
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Jacobs RT, Lunde CS, Freund YR, Hernandez V, Li X, Xia Y, Carter DS, Berry PW, Halladay J, Rock F, Stefanakis R, Easom E, Plattner JJ, Ford L, Johnston KL, Cook DAN, Clare R, Cassidy A, Myhill L, Tyrer H, Gamble J, Guimaraes AF, Steven A, Lenz F, Ehrens A, Frohberger SJ, Koschel M, Hoerauf A, Hübner MP, McNamara CW, Bakowski MA, Turner JD, Taylor MJ, Ward SA. Boron-Pleuromutilins as Anti- Wolbachia Agents with Potential for Treatment of Onchocerciasis and Lymphatic Filariasis. J Med Chem 2019; 62:2521-2540. [PMID: 30730745 PMCID: PMC6421521 DOI: 10.1021/acs.jmedchem.8b01854] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 01/07/2023]
Abstract
A series of pleuromutilins modified by introduction of a boron-containing heterocycle on C(14) of the polycyclic core are described. These analogs were found to be potent anti- Wolbachia antibiotics and, as such, may be useful in the treatment of filarial infections caused by Onchocerca volvulus, resulting in Onchocerciasis or river blindness, or Wuchereria bancrofti and Brugia malayi and related parasitic nematodes resulting in lymphatic filariasis. These two important neglected tropical diseases disproportionately impact patients in the developing world. The lead preclinical candidate compound containing 7-fluoro-6-oxybenzoxaborole (15, AN11251) was shown to have good in vitro anti- Wolbachia activity and physicochemical and pharmacokinetic properties providing high exposure in plasma. The lead was effective in reducing the Wolbachia load in filarial worms following oral administration to mice.
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Affiliation(s)
- Robert T. Jacobs
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Christopher S. Lunde
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Yvonne R. Freund
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Vincent Hernandez
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Xianfeng Li
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Yi Xia
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - David S. Carter
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Pamela W. Berry
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Jason Halladay
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Fernando Rock
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Rianna Stefanakis
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Eric Easom
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Jacob J. Plattner
- Anacor
Pharmaceuticals, 1020
East Meadow Circle, Palo Alto, California 94303, United States
| | - Louise Ford
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Kelly L. Johnston
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Darren A. N. Cook
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Rachel Clare
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Andrew Cassidy
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Laura Myhill
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Hayley Tyrer
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Joanne Gamble
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Ana F. Guimaraes
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Andrew Steven
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Franziska Lenz
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Alexandra Ehrens
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Stefan J. Frohberger
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Marianne Koschel
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Achim Hoerauf
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Marc P. Hübner
- Institute
for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Case W. McNamara
- Calibr, 11119 North
Torrey Pines Road, Suite 100, La Jolla, California 92037, United States
| | - Malina A. Bakowski
- Calibr, 11119 North
Torrey Pines Road, Suite 100, La Jolla, California 92037, United States
| | - Joseph D. Turner
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Mark J. Taylor
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
| | - Stephen A. Ward
- Centre
for Drugs and Diagnostics, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, U.K.
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Voronin D, Tricoche N, Jawahar S, Shlossman M, Bulman CA, Fischer C, Suderman MT, Sakanari JA, Lustigman S. Development of a preliminary in vitro drug screening assay based on a newly established culturing system for pre-adult fifth-stage Onchocerca volvulus worms. PLoS Negl Trop Dis 2019; 13:e0007108. [PMID: 30653499 PMCID: PMC6353222 DOI: 10.1371/journal.pntd.0007108] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 01/30/2019] [Accepted: 12/22/2018] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The human filarial parasite Onchocerca volvulus is the causative agent of onchocerciasis (river blindness). It causes blindness in 270,000 individuals with an additional 6.5 million suffering from severe skin pathologies. Current international control programs focus on the reduction of microfilaridermia by annually administering ivermectin for more than 20 years with the ultimate goal of blocking of transmission. The adult worms of O. volvulus can live within nodules for over 15 years and actively release microfilariae for the majority of their lifespan. Therefore, protracted treatment courses of ivermectin are required to block transmission and eventually eliminate the disease. To shorten the time to elimination of this disease, drugs that successfully target macrofilariae (adult parasites) are needed. Unfortunately, there is no small animal model for the infection that could be used for discovery and screening of drugs against adult O. volvulus parasites. Here, we present an in vitro culturing system that supports the growth and development of O. volvulus young adult worms from the third-stage (L3) infective stage. METHODOLOGY/PRINCIPAL FINDINGS In this study we optimized the culturing system by testing several monolayer cell lines to support worm growth and development. We have shown that the optimized culturing system allows for the growth of the L3 worms to L5 and that the L5 mature into young adult worms. Moreover, these young O. volvulus worms were used in preliminary assays to test putative macrofilaricidal drugs and FDA-approved repurposed drugs. CONCLUSION The culture system we have established for O. volvulus young adult worms offers a promising new platform to advance drug discovery against the human filarial parasite, O. volvulus and thus supports the continuous pursuit for effective macrofilaricidal drugs. However, this in vitro culturing system will have to be further validated for reproducibility before it can be rolled out as a drug screen for decision making in macrofilaricide drug development programs.
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Affiliation(s)
- Denis Voronin
- Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
- * E-mail:
| | - Nancy Tricoche
- Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Shabnam Jawahar
- Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Michael Shlossman
- Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Christina A. Bulman
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Chelsea Fischer
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | | | - Judy A. Sakanari
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Sara Lustigman
- Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
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37
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Short-course, oral flubendazole does not mediate significant efficacy against Onchocerca adult male worms or Brugia microfilariae in murine infection models. PLoS Negl Trop Dis 2019; 13:e0006356. [PMID: 30650071 PMCID: PMC6334903 DOI: 10.1371/journal.pntd.0006356] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/28/2018] [Indexed: 01/15/2023] Open
Abstract
The Onchocerca ochengi adult implant and Brugia malayi microfilariemic Severe-Combined Immunodeficient (SCID) mouse models are validated screens to measure macrofilaricidal and microfilaricidal activities of candidate onchocerciasis drugs. The purpose of this study was to assess whether 5 daily sub-cutaneous (s.c.) injections of standard flubendazole (FBZ) suspension (10mg/kg), a single s.c. injection (10mg/kg) or 5 daily repeated oral doses of FBZ amorphous solid dispersion (ASD) formulation (0.2, 1.5 or 15mg/kg) mediated macrofilaricidal efficacy against O. ochengi male worms implanted into SCID mice. The direct microfilaricidal activity against circulating B. malayi microfilariae of single dose FBZ ASD formulation (2 or 40 mg/kg) was also evaluated and compared against the standard microfilaricide, ivermectin (IVM). Systemic exposures of FBZ/FBZ metabolites achieved following dosing were measured by pharmacokinetic (PK) bioanalysis. At necropsy, five weeks following start of FBZ SC injections, there were significant reductions in burdens of motile O. ochengi worms following multiple injections (93%) or single injection (82%). Further, significant proportions of mice dosed following multiple injections (5/6; 83%) or single injection (6/10; 60%) were infection negative (drug-cured). In comparison, no significant reduction in recovery of motile adult O. ochengi adult worms was obtained in any multiple-oral dosage group. Single oral-dosed FBZ did not mediate any significant microfilaricidal activity against circulating B. malayi mf at 2 or 7 days compared with >80% efficacy of single dose IVM. In conclusion, multiple oral FBZ formulation doses, whilst achieving substantial bioavailability, do not emulate the efficacy delivered by the parenteral route in vivo against adult O. ochengi. PK analysis determined FBZ efficacy was related to sustained systemic drug levels rather than achievable Cmax. PK modelling predicted that oral FBZ would have to be given at low dose for up to 5 weeks in the mouse model to achieve a matching efficacious exposure profile.
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AWZ1066S, a highly specific anti- Wolbachia drug candidate for a short-course treatment of filariasis. Proc Natl Acad Sci U S A 2019; 116:1414-1419. [PMID: 30617067 PMCID: PMC6347715 DOI: 10.1073/pnas.1816585116] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Onchocerciasis (river blindness) and lymphatic filariasis (elephantiasis) are neglected tropical diseases that cause severe disability and affect more than 157 million people globally. Current control efforts are hindered by the lack of a safe macrofilaricidal drug that can eliminate the parasitic adult nematodes safely. A clinically validated approach for delivering macrofilaricidal activity is to target the Wolbachia bacterial endosymbiont of the causative nematodes. This first-in-class and highly potent and specific anti-Wolbachia preclinical candidate molecule, AWZ1066S, has the potential to significantly impact current global onchocerciasis and lymphatic filariasis elimination programs and reduce elimination time frames from decades to years. Onchocerciasis and lymphatic filariasis are two neglected tropical diseases that together affect ∼157 million people and inflict severe disability. Both diseases are caused by parasitic filarial nematodes with elimination efforts constrained by the lack of a safe drug that can kill the adult filaria (macrofilaricide). Previous proof-of-concept human trials have demonstrated that depleting >90% of the essential nematode endosymbiont bacterium, Wolbachia, using antibiotics, can lead to permanent sterilization of adult female parasites and a safe macrofilaricidal outcome. AWZ1066S is a highly specific anti-Wolbachia candidate selected through a lead optimization program focused on balancing efficacy, safety and drug metabolism/pharmacokinetic (DMPK) features of a thienopyrimidine/quinazoline scaffold derived from phenotypic screening. AWZ1066S shows superior efficacy to existing anti-Wolbachia therapies in validated preclinical models of infection and has DMPK characteristics that are compatible with a short therapeutic regimen of 7 days or less. This candidate molecule is well-positioned for onward development and has the potential to make a significant impact on communities affected by filariasis.
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Patton JB, Bennuru S, Eberhard ML, Hess JA, Torigian A, Lustigman S, Nutman TB, Abraham D. Development of Onchocerca volvulus in humanized NSG mice and detection of parasite biomarkers in urine and serum. PLoS Negl Trop Dis 2018; 12:e0006977. [PMID: 30540742 PMCID: PMC6306240 DOI: 10.1371/journal.pntd.0006977] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 12/26/2018] [Accepted: 11/07/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The study of Onchocerca volvulus has been limited by its host range, with only humans and non-human primates shown to be susceptible to the full life cycle infection. Small animal models that support the development of adult parasites have not been identified. METHODOLOGY/PRINCIPAL FINDINGS We hypothesized that highly immunodeficient NSG mice would support the survival and maturation of O. volvulus and alteration of the host microenvironment through the addition of various human cells and tissues would further enhance the level of parasite maturation. NSG mice were humanized with: (1) umbilical cord derived CD34+ stem cells, (2) fetal derived liver, thymus and CD34+ stem cells or (3) primary human skeletal muscle cells. NSG and humanized NSG mice were infected with 100 O. volvulus infective larvae (L3) for 4 to 12 weeks. When necropsies of infected animals were performed, it was observed that parasites survived and developed throughout the infection time course. In each of the different humanized mouse models, worms matured from L3 to advanced fourth stage larvae, with both male and female organ development. In addition, worms increased in length by up to 4-fold. Serum and urine, collected from humanized mice for identification of potential biomarkers of infection, allowed for the identification of 10 O. volvulus-derived proteins found specifically in either the urine or the serum of the humanized O. volvulus-infected NSG mice. CONCLUSIONS/SIGNIFICANCE The newly identified mouse models for onchocerciasis will enable the development of O. volvulus specific biomarkers, screening for new therapeutic approaches and potentially studying the human immune response to infection with O. volvulus.
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Affiliation(s)
- John B. Patton
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia Pennsylvania, United States of America
| | - Sasisekhar Bennuru
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Mark L. Eberhard
- Division of Parasitic Diseases and Malaria, CDC, Atlanta, Georgia, United States of America
| | - Jessica A. Hess
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia Pennsylvania, United States of America
| | - April Torigian
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia Pennsylvania, United States of America
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Thomas B. Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - David Abraham
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia Pennsylvania, United States of America
- * E-mail:
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Zofou D, Fombad FF, Gandjui NVT, Njouendou AJ, Kengne-Ouafo AJ, Chounna Ndongmo PW, Datchoua-Poutcheu FR, Enyong PA, Bita DT, Taylor MJ, Turner JD, Wanji S. Evaluation of in vitro culture systems for the maintenance of microfilariae and infective larvae of Loa loa. Parasit Vectors 2018; 11:275. [PMID: 29716646 PMCID: PMC5930665 DOI: 10.1186/s13071-018-2852-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/16/2018] [Indexed: 01/28/2023] Open
Abstract
Background Suitable and scalable in vitro culture conditions for parasite maintenance are needed to foster drug research for loiasis, one of the neglected tropical diseases which has attracted only limited attention over recent years, despite having important public health impacts. The present work aims to develop adequate in vitro culture systems for drug screening against both microfilariae (mf) and infective third-stage larvae (L3) of Loa loa. Methods In vitro culture conditions were evaluated by varying three basic culture media: Roswell Park Memorial Institute (RPMI-1640), Dulbecco’s modified Eagle’s medium (DMEM) and Iscove’s modified Dulbecco’s medium (IMDM); four sera/proteins: newborn calf serum (NCS), foetal bovine serum (FBS), bovine serum albumin (BSA) and the lipid-enriched BSA (AlbuMax® II, ALB); and co-culture with the Monkey Kidney Epithelial Cell line (LLC-MK2) as a feeder layer. The various culture systems were tested on both mf and L3, using survival (% motile), motility (T90 = mean duration (days) at which at least 90% of parasites were fully active) and moulting rates of L3 as the major criteria. The general linear model regression analysis was performed to assess the contribution of each variable on the viability of Loa loa L3 and microfilarie. All statistical tests were performed at 95% confidence interval. Results Of the three different media tested, DMEM and IMDM were the most suitable sustaining the maintenance of both L. loa L3 and mf. IMDM alone could sustain L3 for more than 5 days (T90 = 6.5 ± 1.1 day). Serum supplements and LLC-MK2 co-cultures significantly improved the survival of parasites in DMEM and IMDM. In co-cultures with LLC-MK2 cells, L. loa mf were maintained in each of the three basic media (T90 of 16.4–19.5 days) without any serum supplement. The most effective culture systems promoting significant moulting rate of L3 into L4 (at least 25%) with substantial maintenance time were: DMEM + BSA, DMEM + NCS, DMEM-AlbuMax®II, DMEM + FBS all in co-culture with LLC-MK2, and IMDM + BSA (1.5%), DMEM + FBS (10%) and DMEM + NCS (5%) without feeder cells. DMEM + 1% BSA in co-culture scored the highest moulting rate of 57 of 81 (70.37%). The factors that promoted L. loa mf viability included feeder cells (β = 0.490), both IMDM (β = 0.256) and DMEM (β = 0.198) media and the protein supplements NCS (β = 0.052) and FBS (β = 0.022); while for L. loa L3, in addition to feeder cells (β = 0.259) and both IMDM (β = 0.401) and DMEM (β = 0.385) media, the protein supplements BSA (β = 0.029) were found important in maintaining the worm motility. Conclusions The findings from this work display a range of culture requirements for the maintenance of Loa loa stages, which are suitable for developing an effective platform for drug screening. Electronic supplementary material The online version of this article (10.1186/s13071-018-2852-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Denis Zofou
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Biotechnology Unit, Faculty of Science, University of Buea, Buea, Cameroon
| | - Fanny Fri Fombad
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | - Narcisse V T Gandjui
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | - Abdel Jelil Njouendou
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | - Arnaud Jonas Kengne-Ouafo
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | - Patrick W Chounna Ndongmo
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | | | - Peter A Enyong
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon
| | - Dizzle Tayong Bita
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon.,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon
| | - Mark J Taylor
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Joseph D Turner
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Samuel Wanji
- Research Foundation for Tropical Diseases and Environment (REFOTDE), South West Region, Buea, Cameroon. .,Parasites and Vectors Biology Research Unit (PAVBRU), Department of Microbiology and Parasitology, Faculty of Science, University of Buea, South West Region, Buea, Cameroon.
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Validation of ultrasound bioimaging to predict worm burden and treatment efficacy in preclinical filariasis drug screening models. Sci Rep 2018; 8:5910. [PMID: 29651095 PMCID: PMC5897408 DOI: 10.1038/s41598-018-24294-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 03/21/2018] [Indexed: 11/22/2022] Open
Abstract
Filariasis is a global health problem targeted for elimination. Curative drugs (macrofilaricides) are required to accelerate elimination. Candidate macrofilaricides require testing in preclinical models of filariasis. The incidence of infection failures and high intra-group variation means that large group sizes are required for drug testing. Further, a lack of accurate, quantitative adult biomarkers results in protracted timeframes or multiple groups for endpoint analyses. Here we evaluate intra-vital ultrasonography (USG) to identify B. malayi in the peritonea of gerbils and CB.17 SCID mice and assess prognostic value in determining drug efficacy. USG operators, blinded to infection status, could detect intra-peritoneal filarial dance sign (ipFDS) with 100% specificity and sensitivity, when >5 B. malayi worms were present in SCID mice. USG ipFDS was predictive of macrofilaricidal activity in randomized, blinded studies comparing flubendazole, albendazole and vehicle-treated SCID mice. Semi-quantification of ipFDS could predict worm burden >10 with 87–100% accuracy in SCID mice or gerbils. We estimate that pre-assessment of worm burden by USG could reduce intra-group variation, obviate the need for surgical implantations in gerbils, and reduce total SCID mouse use by 40%. Thus, implementation of USG may reduce animal use, refine endpoints and negate invasive techniques for assessing anti-filarial drug efficacy.
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Turner JD, Pionnier N, Furlong-Silva J, Sjoberg H, Cross S, Halliday A, Guimaraes AF, Cook DAN, Steven A, Van Rooijen N, Allen JE, Jenkins SJ, Taylor MJ. Interleukin-4 activated macrophages mediate immunity to filarial helminth infection by sustaining CCR3-dependent eosinophilia. PLoS Pathog 2018; 14:e1006949. [PMID: 29547639 PMCID: PMC5874077 DOI: 10.1371/journal.ppat.1006949] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 03/28/2018] [Accepted: 02/26/2018] [Indexed: 12/18/2022] Open
Abstract
Eosinophils are effectors in immunity to tissue helminths but also induce allergic immunopathology. Mechanisms of eosinophilia in non-mucosal tissues during infection remain unresolved. Here we identify a pivotal function of tissue macrophages (Mϕ) in eosinophil anti-helminth immunity using a BALB/c mouse intra-peritoneal Brugia malayi filarial infection model. Eosinophilia, via C-C motif chemokine receptor (CCR)3, was necessary for immunity as CCR3 and eosinophil impairments rendered mice susceptible to chronic filarial infection. Post-infection, peritoneal Mϕ populations proliferated and became alternatively-activated (AAMϕ). Filarial AAMϕ development required adaptive immunity and interleukin-4 receptor-alpha. Depletion of Mϕ prior to infection suppressed eosinophilia and facilitated worm survival. Add back of filarial AAMϕ in Mϕ-depleted mice recapitulated a vigorous eosinophilia. Transfer of filarial AAMϕ into Severe-Combined Immune Deficient mice mediated immunological resistance in an eosinophil-dependent manner. Exogenous IL-4 delivery recapitulated tissue AAMϕ expansions, sustained eosinophilia and mediated immunological resistance in Mϕ-intact SCID mice. Co-culturing Brugia with filarial AAMϕ and/or filarial-recruited eosinophils confirmed eosinophils as the larvicidal cell type. Our data demonstrates that IL-4/IL-4Rα activated AAMϕ orchestrate eosinophil immunity to filarial tissue helminth infection. Helminths parasitize approximately one quarter of the global population. Medically-important helminths, including filariae responsible for elephantiasis and river blindness, are targeted for elimination as a public health problem. Currently there are no vaccines or immunotherapeutics available for filarial worms or other human helminth pathogens. Here we define a cellular mechanism whereby the interlukin-4 dependent activation of tissue macrophages are essential to sustain the recruitment of larvicidal eosinophil granulocytes, leading to immunity against filarial infection at a sterile tissue site of parasitism. This work delineates the relative non-redundant functional roles of both myeloid cell types in ‘type-2’ immunity to helminth infection. The study represents a mechanistic advance in our understanding of how immunity operates against metazoan macroparasites invading sterile tissues and may be used in the rational design of new therapeutics to limit helminth disease.
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Affiliation(s)
- Joseph D. Turner
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- * E-mail:
| | - Nicolas Pionnier
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Julio Furlong-Silva
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Hanna Sjoberg
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Stephen Cross
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Alice Halliday
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Ana F. Guimaraes
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Darren A. N. Cook
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Andrew Steven
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nico Van Rooijen
- VU University Medical Center, Department of Molecular Cell Biology and Immunology, Amsterdam, Netherlands
| | - Judith E. Allen
- Faculty of Biology, Medicine & Health, University of Manchester, Manchester, United Kingdom
| | - Stephen J. Jenkins
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Mark J. Taylor
- Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Specht S, Pfarr KM, Arriens S, Hübner MP, Klarmann-Schulz U, Koschel M, Sternberg S, Martin C, Ford L, Taylor MJ, Hoerauf A. Combinations of registered drugs reduce treatment times required to deplete Wolbachia in the Litomosoides sigmodontis mouse model. PLoS Negl Trop Dis 2018; 12:e0006116. [PMID: 29300732 PMCID: PMC5771630 DOI: 10.1371/journal.pntd.0006116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 01/17/2018] [Accepted: 11/15/2017] [Indexed: 01/22/2023] Open
Abstract
Filarial parasites can be targeted by antibiotic treatment due to their unique endosymbiotic relationship with Wolbachia bacteria. This finding has led to successful treatment strategies in both, human onchocerciasis and lymphatic filariasis. A 4–6 week treatment course using doxycycline results in long-term sterility and safe macrofilaricidal activity in humans. However, current treatment times and doxycycline contraindications in children and pregnant women preclude widespread administration of doxycycline in public health control programs; therefore, the search for shorter anti-wolbachial regimens is a focus of ongoing research. We have established an in vivo model for compound screening, using mice infected with Litomosoides sigmodontis. We could show that gold standard doxycycline treatment did not only deplete Wolbachia, it also resulted in a larval arrest. In this model, combinations of registered antibiotics were tested for their anti-wolbachial activity. Administration of rifamycins in combination with doxycycline for 7 days successfully depleted Wolbachia by > 2 log (>99% reduction) and thus resulted in a significant reduction of the treatment duration. Using a triple combination of a tetracycline (doxycycline or minocycline), a rifamycin and a fluoroquinolone (moxifloxacin) led to an even greater shortening of the treatment time. Testing all double combinations that could be derived from the triple combinations revealed that the combination of rifapentine (15mg/kg) and moxifloxacin (2 x 200mg/kg) showed the strongest reduction of treatment time in intraperitoneal and also oral administration routes. The rifapentine plus moxifloxacin combination was equivalent to the triple combination with additional doxycycline (>99% Wolbachia reduction). These investigations suggest that it is possible to shorten anti-wolbachial treatment times with combination treatments in order to achieve the target product profile (TPP) requirements for macrofilaricidal drugs of no more than 7–10 days of treatment. Over the past years, more attention has been brought to neglected tropical diseases including lymphatic filariasis and onchocerciasis. The latter are caused by helminthic parasites and lead to chronic and debilitating symptoms and present a major health burden that also affects the economy of endemic countries. It has been suggested that disease elimination may be possible but an accelerated implementation of proven and cost-effective interventions are needed if the targets for elimination are to be achieved. Recently, an indirect mode of action has been identified, targeting bacterial Wolbachia endosymbionts within the filariae, which also kills the adult parasites, an advantage over the drug currently used for mass drug administration, i.e. ivermectin. Doxycycline has been successfully used in clinical trials, however due to its long regimen as well as restrictions of use in children and pregnant women new drugs or drug combinations are required that overcome these obstacles. Here, we present the filarial parasite Litomosoides sigmodontis as suitable model for the preclinical testing of anti-wolbachial drugs against filariae and show that combinations of already registered drugs with anti-wolbachial efficacy are able to reduce the treatment time dramatically.
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Affiliation(s)
- Sabine Specht
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- Institute for Laboratory Animal Science, Vetsuisse Faculty, University of Zurich, Switzerland
- * E-mail:
| | - Kenneth M. Pfarr
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Centre for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Sandra Arriens
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Marc P. Hübner
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Ute Klarmann-Schulz
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Centre for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Marianne Koschel
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Sonja Sternberg
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Coralie Martin
- UMR 7245 MCAM MNHN CNRS, Museum National d`Histoire Naturelle, Paris, France
| | - Louise Ford
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Mark J. Taylor
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Centre for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
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Albendazole and antibiotics synergize to deliver short-course anti- Wolbachia curative treatments in preclinical models of filariasis. Proc Natl Acad Sci U S A 2017; 114:E9712-E9721. [PMID: 29078351 PMCID: PMC5692564 DOI: 10.1073/pnas.1710845114] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Filarial nematode infections, caused by Wuchereria bancrofti, Brugia malayi (elephantiasis), and Onchocerca volvulus (river blindness) infect 150 million of the world’s poorest populations and cause profound disability. Standard treatments require repetitive, long-term, mass drug administrations and have failed to interrupted transmission in certain sub-Saharan African regions. A drug cure using doxycycline, which targets the essential filarial endosymbiont Wolbachia, is clinically effective but programmatically challenging to implement due to long treatment durations and contraindications. Here we provide proof-of-concept of a radical improvement of targeting Wolbachia via identification of drug synergy between the anthelmintic albendazole and antibiotics. This synergy enables the shortening of treatment duration of macrofilaricidal anti-Wolbachia based treatments from 4 wk to 7 d with registered drugs ready for clinical testing. Elimination of filariasis requires a macrofilaricide treatment that can be delivered within a 7-day period. Here we have identified a synergy between the anthelmintic albendazole (ABZ) and drugs depleting the filarial endosymbiont Wolbachia, a proven macrofilaricide target, which reduces treatment from several weeks to 7 days in preclinical models. ABZ had negligible effects on Wolbachia but synergized with minocycline or rifampicin (RIF) to deplete symbionts, block embryogenesis, and stop microfilariae production. Greater than 99% Wolbachia depletion following 7-day combination of RIF+ABZ also led to accelerated macrofilaricidal activity. Thus, we provide preclinical proof-of-concept of treatment shortening using antibiotic+ABZ combinations to deliver anti-Wolbachia sterilizing and macrofilaricidal effects. Our data are of immediate public health importance as RIF+ABZ are registered drugs and thus immediately implementable to deliver a 1-wk macrofilaricide. They also suggest that novel, more potent anti-Wolbachia drugs under development may be capable of delivering further treatment shortening, to days rather than weeks, if combined with benzimidazoles.
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Affiliation(s)
- Sara Lustigman
- Molecular Parasitology, New York Blood Center, New York, NY, United States of America
- * E-mail:
| | - Alexandra Grote
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, United States of America
| | - Elodie Ghedin
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, United States of America
- College of Global Public Health, New York University, New York, NY, United States of America
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Aljayyoussi G, Tyrer HE, Ford L, Sjoberg H, Pionnier N, Waterhouse D, Davies J, Gamble J, Metuge H, Cook DAN, Steven A, Sharma R, Guimaraes AF, Clare RH, Cassidy A, Johnston KL, Myhill L, Hayward L, Wanji S, Turner JD, Taylor MJ, Ward SA. Short-Course, High-Dose Rifampicin Achieves Wolbachia Depletion Predictive of Curative Outcomes in Preclinical Models of Lymphatic Filariasis and Onchocerciasis. Sci Rep 2017; 7:210. [PMID: 28303006 PMCID: PMC5428297 DOI: 10.1038/s41598-017-00322-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/21/2017] [Indexed: 12/29/2022] Open
Abstract
Lymphatic filariasis (LF) and onchocerciasis are priority neglected tropical diseases targeted for elimination. The only safe drug treatment with substantial curative activity against the filarial nematodes responsible for LF (Brugia malayi, Wuchereria bancrofti) or onchocerciasis (Onchocerca volvulus) is doxycycline. The target of doxycycline is the essential endosymbiont, Wolbachia. Four to six weeks doxycycline therapy achieves >90% depletion of Wolbachia in worm tissues leading to blockade of embryogenesis, adult sterility and premature death 18-24 months post-treatment. Long treatment length and contraindications in children and pregnancy are obstacles to implementing doxycycline as a public health strategy. Here we determine, via preclinical infection models of Brugia malayi or Onchocerca ochengi that elevated exposures of orally-administered rifampicin can lead to Wolbachia depletions from filariae more rapidly than those achieved by doxycycline. Dose escalation of rifampicin achieves >90% Wolbachia depletion in time periods of 7 days in B. malayi and 14 days in O. ochengi. Using pharmacokinetic-pharmacodynamic modelling and mouse-human bridging analysis, we conclude that clinically relevant dose elevations of rifampicin, which have recently been determined as safe in humans, could be administered as short courses to filariasis target populations with potential to reduce anti-Wolbachia curative therapy times to between one and two weeks.
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Affiliation(s)
- Ghaith Aljayyoussi
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Hayley E Tyrer
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Louise Ford
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Hanna Sjoberg
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Nicolas Pionnier
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - David Waterhouse
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Jill Davies
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Joanne Gamble
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Haelly Metuge
- Research Foundation in Tropical Medicine and the Environment, Buea, Cameroon
- Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Darren A N Cook
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Andrew Steven
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Raman Sharma
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Ana F Guimaraes
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Rachel H Clare
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Andrew Cassidy
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Kelly L Johnston
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Laura Myhill
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Laura Hayward
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Samuel Wanji
- Research Foundation in Tropical Medicine and the Environment, Buea, Cameroon
- Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Joseph D Turner
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Mark J Taylor
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Stephen A Ward
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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47
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Mbah GE, Ayiseh RB, Cho-Ngwa F. Development and validation of an Onchocerca ochengi microfilarial hamster model for onchocerciasis drug screens. BMC Infect Dis 2016; 16:404. [PMID: 27515037 PMCID: PMC4982420 DOI: 10.1186/s12879-016-1753-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 08/04/2016] [Indexed: 12/02/2022] Open
Abstract
Background Onchocerciasis, caused by the parasitic nematode, Onchocerca volvulus afflicts some 37 million people worldwide, and is the second leading infectious cause of blindness globally. The only currently recommended drug for treatment of the disease, ivermectin, is only microfilaricidal and has serious adverse effects in individuals co-infected with high loads of Loa loa microfilariae (mf), prompting the search for new and better drugs. Onchocerciasis drug discovery studies have so far been based on in vivo models using Onchocerca species which are not the closest to O. volvulus, and which may therefore, not adequately mimic the natural infection in humans. Therefore, this study was carried out to develop a better drug screening model for onchocerciasis, based on the use of cow-derived O. ochengi, the closest known relative of O. volvulus. Methods Mf of O. ochengi were injected subcutaneously at the nape of Syrian hamsters (Mesocricetus auratus) and BALB/c mice. The skin, and especially the earlobes of the animals were examined for mf 15–31 days after infection. For selected model validation, the hamsters were treated with ivermectin at 150 or 600 μg/kg body weight and examined 30 days after infection for mf. For L. loa studies in hamsters, isolated mf were injected intraperitoneally and animal organs were examined on day 26 for mf. Results The Syrian hamsters were found to be the more permissive to O. ochengi mf as fully viable mf were recovered from them on day 30, compared to BALB/c mice where such mf were recovered on day 15, but not 30. However, both animals were not permissive to L. loa mf even by day 15. Interestingly, more than 50 % of the total O. ochengi mf recovered were from the earlobes. The number of mf injected was directly proportional to the number recovered. Ivermectin at both concentrations tested completely eliminated the O. ochengi mf from the hamsters. Conclusion This study reveals the Syrian hamster as an appropriate small animal model for screening of novel compounds against O. ochengi, the closest known relative of O. volvulus.
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Affiliation(s)
- Glory Enjong Mbah
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, South West Region, Cameroon
| | - Rene Bilingwe Ayiseh
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, South West Region, Cameroon
| | - Fidelis Cho-Ngwa
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea, South West Region, Cameroon.
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48
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Sharma R, Al Jayoussi G, Tyrer HE, Gamble J, Hayward L, Guimaraes AF, Davies J, Waterhouse D, Cook DAN, Myhill LJ, Clare RH, Cassidy A, Steven A, Johnston KL, Ford L, Turner JD, Ward SA, Taylor MJ. Minocycline as a re-purposed anti-Wolbachia macrofilaricide: superiority compared with doxycycline regimens in a murine infection model of human lymphatic filariasis. Sci Rep 2016; 6:23458. [PMID: 26996237 PMCID: PMC4800446 DOI: 10.1038/srep23458] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/07/2016] [Indexed: 12/03/2022] Open
Abstract
Lymphatic filariasis and onchocerciasis are parasitic helminth diseases, which cause severe morbidities such as elephantiasis, skin disease and blindness, presenting a major public health burden in endemic communities. The anti-Wolbachia consortium (A·WOL: http://www.a-wol.com/) has identified a number of registered antibiotics that target the endosymbiotic bacterium, Wolbachia, delivering macrofilaricidal activity. Here we use pharmacokinetics/pharmacodynamics (PK/PD) analysis to rationally develop an anti-Wolbachia chemotherapy by linking drug exposure to pharmacological effect. We compare the pharmacokinetics and anti-Wolbachia efficacy in a murine Brugia malayi model of minocycline versus doxycycline. Doxycycline exhibits superior PK in comparison to minocycline resulting in a 3-fold greater exposure in SCID mice. Monte-Carlo simulations confirmed that a bi-daily 25–40 mg/Kg regimen is bioequivalent to a clinically effective 100–200 mg/day dose for these tetracyclines. Pharmacodynamic studies showed that minocycline depletes Wolbachia more effectively than doxycycline (99.51% vs. 90.35%) after 28 day 25 mg/Kg bid regimens with a more potent block in microfilarial production. PK/PD analysis predicts that minocycline would be expected to be 1.7 fold more effective than doxycycline in man despite lower exposure in our infection models. Our findings warrant onward clinical investigations to examine the clinical efficacy of minocycline treatment regimens against lymphatic filariasis and onchocerciasis.
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Affiliation(s)
- Raman Sharma
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Ghaith Al Jayoussi
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Hayley E Tyrer
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Joanne Gamble
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Laura Hayward
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Ana F Guimaraes
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Jill Davies
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - David Waterhouse
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Darren A N Cook
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Laura J Myhill
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Rachel H Clare
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Andrew Cassidy
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Andrew Steven
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Kelly L Johnston
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Louise Ford
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Joseph D Turner
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Stephen A Ward
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Mark J Taylor
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
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49
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Globisch D, Specht S, Pfarr KM, Eubanks LM, Hoerauf A, Janda KD. Litomosoides sigmodontis: a jird urine metabolome study. Bioorg Med Chem Lett 2015; 25:5804-7. [PMID: 26573416 DOI: 10.1016/j.bmcl.2015.10.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 10/14/2015] [Indexed: 12/26/2022]
Abstract
The neglected tropical disease onchocerciasis affects more than 35 million people worldwide with over 95% in Africa. Disease infection initiates from the filarial parasitic nematode Onchocerca volvulus, which is transmitted by the blackfly vector Simulium sp. carrying infectious L3 larvae. New treatments and diagnostics are required to eradicate this parasitic disease. Herein, we describe that a previously discovered biomarker for onchocerciasis, N-acetyltyramine-O-glucuronide (NATOG) is also present in urine samples of jirds infected with the onchocerciasis model nematode Litomosoides sigmodontis. Increased NATOG values paralleled a progressing infection and demonstrated that quantification of NATOG in this rodent model can be utilized to track its infectivity. Moreover, our findings suggest how NATOG monitoring may be used for evaluating potential drug candidates.
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Affiliation(s)
- Daniel Globisch
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States; Department of Immunology, The Skaggs Institute for Chemical Biology, The Worm Institute of Research and Medicine (WIRM), The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States
| | - Sabine Specht
- Institute of Medical Microbiology, Immunology, and Parasitology (IMMIP), University Hospital Bonn, Sigmund Freud Straße 25, 53105 Bonn, Germany
| | - Kenneth M Pfarr
- Institute of Medical Microbiology, Immunology, and Parasitology (IMMIP), University Hospital Bonn, Sigmund Freud Straße 25, 53105 Bonn, Germany
| | - Lisa M Eubanks
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States; Department of Immunology, The Skaggs Institute for Chemical Biology, The Worm Institute of Research and Medicine (WIRM), The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States
| | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology, and Parasitology (IMMIP), University Hospital Bonn, Sigmund Freud Straße 25, 53105 Bonn, Germany
| | - Kim D Janda
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States; Department of Immunology, The Skaggs Institute for Chemical Biology, The Worm Institute of Research and Medicine (WIRM), The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, United States.
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50
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Al-Abd NM, Nor ZM, Ahmed A, Al-Adhroey AH, Mansor M, Kassim M. Lymphatic filariasis in Peninsular Malaysia: a cross-sectional survey of the knowledge, attitudes, and practices of residents. Parasit Vectors 2014; 7:545. [PMID: 25428558 PMCID: PMC4253608 DOI: 10.1186/s13071-014-0545-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 11/17/2014] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Lymphatic filariasis (LF) is a major cause of permanent disability in many tropical and sub-tropical countries of the world. Malaysia is one of the countries in which LF is an endemic disease. Five rounds of the mass drug administration (MDA) program have been conducted in Malaysia as part of the Global Program to Eliminate Lymphatic Filariasis (GPELF) by year 2020. This study investigated the level of awareness of LF and the MDA program in a population living in an endemic area of the country. METHODS A descriptive cross-sectional survey that involved 230 respondents (≥15 years old) living in the LF endemic communities of Terengganu state in Peninsular Malaysia was performed. Demographic, socioeconomic, and knowledge, attitudes and practices (KAP) data of the respondents were obtained using pre-tested questionnaires and were analyzed using SPSS software version 13.0. RESULTS More than 80% of the respondents were aware of LF and the common symptoms of the disease. Moreover, about 70% of the respondents that were aware of LF indicated that it is a problematic disease. Approximately 77% of the respondents indicated that filariasis is transmitted by mosquitoes. Two-thirds of respondents preferred hospital treatment for illness; however, only 12% had participated and/or received treatment for LF during an MDA program. Only 35% of the respondents that participated in this research were aware of the MDA program that had taken place in the area. None of the respondents had knowledge of the drug used in the treatment of LF. The findings from this research indicated that there was no significant association between LF awareness and with gender, age group, educational status, occupation, or socio-economic status of the respondents (P >0.05). CONCLUSION A good proportion of the respondents are aware of LF, its mode of transmission and symptoms, however they demonstrated a poor knowledge of MDA which took place in the study area. For greater understanding of LF in the Malaysian population, there is a need for an enhancement in the delivery of health education and information programs and mass mobilization campaigns in endemic communities.
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Affiliation(s)
- Nazeh M Al-Abd
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Zurainee Mohamed Nor
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Abdulhamid Ahmed
- Department of Biology, Faculty of Natural and Applied Sciences, Umaru Musa Yar'adua University, Katsina, Katsina State, Nigeria.
| | - Abdulelah H Al-Adhroey
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Marzida Mansor
- Department of Anesthesiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
| | - Mustafa Kassim
- Department of Anesthesiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia.
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