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Vinkeles Melchers NVS, Agoro S, Togbey K, Padjoudoum K, Telou IG, Karabou P, Djatho T, Datagni M, Dorkenoo AM, Kassankogno Y, Bronzan R, Stolk WA. Impact of ivermectin and vector control on onchocerciasis transmission in Togo: Assessing the empirical evidence on trends in infection and entomological indicators. PLoS Negl Trop Dis 2024; 18:e0012312. [PMID: 39038058 DOI: 10.1371/journal.pntd.0012312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 06/08/2024] [Indexed: 07/24/2024] Open
Abstract
BACKGROUND The World Health Organization's 2021-2030 Road Map for Neglected Tropical Diseases boosted global commitment towards the elimination of onchocerciasis, but the timeline to elimination will vary strongly between countries in Africa. To assess progress towards elimination in the Republic of Togo, we reviewed the history of control and time trends in infection. METHODOLOGY/PRINCIPAL FINDINGS We collated all available programmatic, entomological, and epidemiological data since the initiation of the Onchocerciasis Control Programme (OCP) in Togo through different data sources. We then visualised data trends over time, to assess the impact of interventions on infection and transmission levels. Vector control was initiated by OCP from 1977 (northern and central parts of Togo) or 1988 (southern regions) up to 2002 (most areas) or 2007 ("special intervention zones" [SIZ], parts of Northern and Central Togo). Between 1988 and 1991, Togo initiated ivermectin mass drug administration (MDA) in eligible communities. The impact of vector control was high in most river basins, resulting in low annual biting rates and annual transmission potential declining to very low levels; the impact was lower in river basins designated as SIZ. Repeated, longitudinal ivermectin mass treatments have overall strongly reduced onchocerciasis transmission in Togo. Epidemiological surveys performed between 2014 and 2017 showed that the prevalence of skin microfilariae (mf) and anti-OV16 IgG4 antibodies had declined to low levels in several districts of the Centrale, Plateaux, and Maritime region. Yet, relatively high mf prevalences (between 5.0% and 32.7%) were still found in other districts during the same period, particularly along the Kéran, Mô and Ôti river basins (SIZ areas). CONCLUSIONS/SIGNIFICANCE Trends in infection prevalence and intensity show that onchocerciasis levels have dropped greatly over time in most areas. This demonstrates the large impact of long-term and wide-scale interventions, and suggest that several districts of Togo are approaching elimination.
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Affiliation(s)
- Natalie V S Vinkeles Melchers
- Health & Society Group, Department of Social Sciences, Wageningen University & Research, Hollandseweg 1, Wageningen, The Netherlands
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sibabi Agoro
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Kwamy Togbey
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Koffi Padjoudoum
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Ibrahim Gado Telou
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Potchoziou Karabou
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Touka Djatho
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Michel Datagni
- National Institute of Hygiene, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | | | | | - Rachel Bronzan
- Bill & Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Wilma A Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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Sulik M, Antoszczak M, Huczyński A, Steverding D. Antiparasitic activity of ivermectin: Four decades of research into a "wonder drug". Eur J Med Chem 2023; 261:115838. [PMID: 37793327 DOI: 10.1016/j.ejmech.2023.115838] [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] [Received: 08/22/2023] [Revised: 09/17/2023] [Accepted: 09/26/2023] [Indexed: 10/06/2023]
Abstract
Parasitic diseases still pose a serious threat to human and animal health, particularly for millions of people and their livelihoods in low-income countries. Therefore, research into the development of effective antiparasitic drugs remains a priority. Ivermectin, a sixteen-membered macrocyclic lactone, exhibits a broad spectrum of antiparasitic activities, which, combined with its low toxicity, has allowed the drug to be widely used in the treatment of parasitic diseases affecting humans and animals. In addition to its licensed use against river blindness and strongyloidiasis in humans, and against roundworm and arthropod infestations in animals, ivermectin is also used "off-label" to treat many other worm-related parasitic diseases, particularly in domestic animals. In addition, several experimental studies indicate that ivermectin displays also potent activity against viruses, bacteria, protozoans, trematodes, and insects. This review article summarizes the last 40 years of research on the antiparasitic effects of ivermectin, and the use of the drug in the treatment of parasitic diseases in humans and animals.
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Affiliation(s)
- Michał Sulik
- Department of Medical Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61‒614, Poznań, Poland
| | - Michał Antoszczak
- Department of Medical Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61‒614, Poznań, Poland
| | - Adam Huczyński
- Department of Medical Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61‒614, Poznań, Poland.
| | - Dietmar Steverding
- Bob Champion Research & Education Building, Norwich Medical School, University of East Anglia, Norwich, UK
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Amambo GN, Innocentia N, Abong RA, Fombad FF, Njouendou AJ, Nietcho F, Ekanya R, Kien CA, Ebai R, Lenz B, Ritter M, Esum ME, Deribe K, Cho JF, Beng AA, Enyong PI, Li Z, Hübner MP, Pfarr K, Hoerauf A, Carlow C, Wanji S. Application of loop mediated isothermal amplification (LAMP) assays for the detection of Onchocerca volvulus, Loa loa and Mansonella perstans in humans and vectors. FRONTIERS IN TROPICAL DISEASES 2023; 3:1016176. [PMID: 36684508 PMCID: PMC7614089 DOI: 10.3389/fitd.2022.1016176] [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] [Indexed: 01/11/2023] Open
Abstract
Conventional diagnosis of filarial infections is based on morphological identification of microfilariae using light microscopy and requires considerable expertise, is time-consuming, and can be subjective. Loop-mediated isothermal amplification (LAMP) has advantages over microscopy or PCR because of its operational simplicity, rapidity and versatility of readout options. LAMP assays represent a major step forward in improved filarial diagnostic tools suitable for low resource settings and field applicability. The study goal was to retrospectively evaluate the performance and suitability of the O-150, RF4, and Mp419 LAMP assays for diagnosing Onchocerca volvulus, Loa loa and Mansonella perstans infections, respectively, in humans and vectors under experimental and natural field conditions. Surveys were conducted in four health districts of Cameroon using skin snip and thick blood film methods to detect skin (O. volvulus) and blood (L. loa and M. perstans) dwelling microfilaria in humans. Engorged vectors (Simulium spp., Chrysops spp., and Culicoides spp.) were evaluated by LAMP. Dissected, wild-caught vectors were also analyzed. LAMP showed a prevalence of 40.4% (O. volvulus), 17.8% (L. loa) and 36.6% (M. perstans) versus 20.6% (O. volvulus), 17.4% (L. loa) and 33.8% (M. perstans) with microscopy. Simulium spp. were dissected for microscopy and pooled for LAMP. The O-150 LAMP assay infection rate was 4.3% versus 4.1% by microscopy. Chrysops spp. were dissected and analyzed individually in the LAMP assay. The RF4 LAMP assay infection rate was 23.5% versus 3.3% with microscopy. The RF4 LAMP assay also detected parasites in Chrysops spp. fed on low microfilaremic volunteers. The Mp419 LAMP assay infection rate was 0.2% for C. milnei and 0.04% for C. grahamii, while three other species were LAMP-negative. The sensitivity, species specificity, rapidity and ease of its use of these filarial LAMP assays, and validation of their performance in the field support use as alternatives to microscopy as diagnostic and surveillance tools in global health programs aimed to eliminate onchocerciasis.
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Affiliation(s)
- Glory Ngongeh Amambo
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Ngong Innocentia
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Raphael Awah Abong
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Fanny Fri Fombad
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Abdel Jelil Njouendou
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Department of Biomedical Science, Faculty of Health Sciences, University of Buea, Buea, Cameroon
| | - Franck Nietcho
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Relindis Ekanya
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Chi Anizette Kien
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Rene Ebai
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Benjamin Lenz
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Manuel Ritter
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
| | - Mathias Eyong Esum
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Kebede Deribe
- Global Health and Infection Department, Brighton and Sussex Medical School, Brighton, United Kingdom
- School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Jerome Fru Cho
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Amuam Andrew Beng
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Peter Ivo Enyong
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
| | - Zhiru Li
- New England Biolabs, Ipswich, MA, United States
| | - Marc P. Hübner
- Institute of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Kenneth Pfarr
- Institute of 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 of Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center 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
- Parasites and Vector Research Unit (PAVRU), Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
- Research Foundation in Tropical Diseases and Environment (REFOTDE), Buea, Cameroon
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Johanns SI, Gantin RG, Wangala B, Komlan K, Halatoko WA, Banla M, Karabou P, Luty AJF, Schulz-Key H, Köhler C, Soboslay PT. Onchocerca volvulus-specific antibody and cellular responses in onchocerciasis patients treated annually with ivermectin for 30 years and exposed to parasite transmission in central Togo. PLoS Negl Trop Dis 2022; 16:e0010340. [PMID: 35503786 PMCID: PMC9064110 DOI: 10.1371/journal.pntd.0010340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 03/20/2022] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Annual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients' eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. METHODOLOGY/PRINCIPAL FINDINGS Onchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT). Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients' location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections. CONCLUSIONS/SIGNIFICANCE Repeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission.
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Affiliation(s)
- Saskia I. Johanns
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Richard G. Gantin
- Onchocerciasis Reference Laboratory, Institut National d’Hygiene, Centre Hospitalier Regional, Sokode, Togo
| | - Bawoubadi Wangala
- Onchocerciasis Reference Laboratory, Institut National d’Hygiene, Centre Hospitalier Regional, Sokode, Togo
| | | | | | - Meba Banla
- Centre Hospitalier Universitaire, Université de Lomé, Lomé, Togo
| | | | - Adrian JF Luty
- Université de Paris, Institut de Recherche pour le Développement, Paris, France
| | - Hartwig Schulz-Key
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Carsten Köhler
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Peter T. Soboslay
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
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Ataba E, Katawa G, Ritter M, Ameyapoh AH, Anani K, Amessoudji OM, Tchadié PE, Tchacondo T, Batawila K, Ameyapoh Y, Hoerauf A, Layland LE, Karou SD. Ethnobotanical survey, anthelmintic effects and cytotoxicity of plants used for treatment of helminthiasis in the Central and Kara regions of Togo. BMC Complement Med Ther 2020; 20:212. [PMID: 32635909 PMCID: PMC7341664 DOI: 10.1186/s12906-020-03008-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 06/26/2020] [Indexed: 01/26/2023] Open
Abstract
Background Traditional medicines are the main source of treatment of helminthiasis in endemic areas of Togo. The present study aimed to investigate the plants used by Traditional healers (THs) to treat helminth infections in endemic communities within the Central and Kara regions of Togo and to evaluate the anthelmintic activity of the three most cited plants. Methods An ethnobotanical survey was conducted from 19 to 24 June 2017 among traditional healers in the Central and Kara regions of Togo. The anthelmintic activity of the most cited plants namely Aframomum melegueta K. Schum, Khaya senegalensis A. Juss and Xylopia aethiopica A. Rich, was evaluated using microfilariae (Mf) of Litomosoides sigmodontis. The plants were evaluated for cytotoxicity according to the recommendation of NF EN ISO 10993-5 standard using the propidium iodide (PI) dye by flow cytometry on human peripheral blood mononuclear cells. Results A total of 197 THs were interviewed and 41 plant species were recorded. Leguminosae (14.6%) and Annonaceae (9.7%) families constitute the highest number of species cited for treatment of helminth infections. Afromomum melegueta was the most cited by the THs for the treatment of onchocerciasis (UV = 0.036) while X. aethiopica was associated with the treatment of schistosomiasis (UV = 0.061) and lymphatic filariasis (UV = 0.061). There was a great agreement among the THs regarding ethnomedicinal uses of plants to treat helminthiasis with ICF values ranging from 0.57 to 0.67. The anthelmintic assay yielded lethal doses values of 233 μg/mL, 265 μg/mL and 550 μg/mL, respectively for X. aethiopica, A. melegueta and K. senegalensis. Afromomum melegueta and X. aethiopica presented no cytotoxicity, less than 20% death, whereas K. senegalensis induced moderate toxicity, 24 ± 8% death. Conclusion This study demonstrated the scientific rationale for the use of plants to treat helminthiasis in the Togolese traditional medicine. However, the use of K. senegalensis requires more caution since the plant is fairly toxic. Trial Registration NA
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Affiliation(s)
- Essoham Ataba
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Gnatoulma Katawa
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Manuel Ritter
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany
| | - Adjoa Holali Ameyapoh
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Kokou Anani
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Oukoe M Amessoudji
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Pélagie Edlom Tchadié
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Tchadjabo Tchacondo
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Komlan Batawila
- Laboratoire de Biologie et Ecologie Végétale, Faculté des Sciences (FDS), Université de Lomé, Lomé, Togo
| | - Yaovi Ameyapoh
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany.,German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Laura E Layland
- Institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany.,German Center for Infection Research (DZIF), partner site Bonn-Cologne, Bonn, Germany
| | - Simplice D Karou
- Ecole Supérieure des Techniques Biologiques et Alimentaires (ESTBA)/Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires/Unité de Recherche en Immunologie et Immunomodulation (UR2IM), Université de Lomé, 01 BP 1515, Lomé, Togo.
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In Silico Identification of Novel Biomarkers and Development of New Rapid Diagnostic Tests for the Filarial Parasites Mansonella perstans and Mansonella ozzardi. Sci Rep 2019; 9:10275. [PMID: 31311985 PMCID: PMC6635353 DOI: 10.1038/s41598-019-46550-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/29/2019] [Indexed: 02/02/2023] Open
Abstract
Mansonelliasis is a widespread yet neglected tropical infection of humans in Africa and South America caused by the filarial nematodes, Mansonella perstans, M. ozzardi, M. rodhaini and M. streptocerca. Clinical symptoms are non-distinct and diagnosis mainly relies on the detection of microfilariae in skin or blood. Species-specific DNA repeat sequences have been used as highly sensitive biomarkers for filarial nematodes. We have developed a bioinformatic pipeline to mine Illumina reads obtained from sequencing M. perstans and M. ozzardi genomic DNA for new repeat biomarker candidates which were used to develop loop-mediated isothermal amplification (LAMP) diagnostic tests. The M. perstans assay based on the Mp419 repeat has a limit of detection of 0.1 pg, equivalent of 1/1000th of a microfilaria, while the M. ozzardi assay based on the Mo2 repeat can detect as little as 0.01 pg. Both LAMP tests possess remarkable species-specificity as they did not amplify non-target DNAs from closely related filarial species, human or vectors. We show that both assays perform successfully on infected human samples. Additionally, we demonstrate the suitability of Mp419 to detect M. perstans infection in Culicoides midges. These new tools are field deployable and suitable for the surveillance of these understudied filarial infections.
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Wangala B, Gantin RG, Voßberg PS, Vovor A, Poutouli WP, Komlan K, Banla M, Köhler C, Soboslay PT. Inflammatory and regulatory CCL and CXCL chemokine and cytokine cellular responses in patients with patent Mansonella perstans filariasis. Clin Exp Immunol 2019; 196:111-122. [PMID: 30561772 DOI: 10.1111/cei.13251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2018] [Indexed: 12/17/2022] Open
Abstract
Mansonella perstans (Mp) filariasis is present in large populations in sub-Saharan Africa, and to what extent patent Mp infection modulates the expression of immunity in patients, notably their cellular cytokine and chemokine response profile, remains not well known. We studied the spontaneous and inducible cellular production of chemokines (C-X-C motif) ligand 9 (CXCL9) [monokine induced by interferon (IFN)-γ (MIG)], CXCL-10 [inducible protein (IP)-10], chemokine (C-C motif) ligand 24 (CCL24) (eotaxin-2), CCL22 [macrophage-derived chemokine (MDC)], CCL13 [monocyte chemotactic protein-4 (MCP-4)], CCL18 [pulmonary and activation-regulated chemokine (PARC)], CCL17 [thymus- and activation-regulated chemokine (TARC)] and interleukin (IL)-27 in mansonelliasis patients (Mp-PAT) and mansonelliasis-free controls (CTRL). Freshly isolated peripheral mononuclear blood cells (PBMC) were stimulated with helminth, protozoan and bacterial antigens and mitogen [phytohaemagglutinin (PHA)]. PBMC from Mp-PAT produced spontaneously (without antigen stimulation) significantly higher levels of eotaxin-2, IL-27, IL-8, MCP-4 and MDC than cells from CTRL, while IFN-γ-IP-10 was lower in Mp-PAT. Helminth antigens activated IL-27 and MCP-4 only in CTRL, while Ascaris antigen, Onchocerca antigen, Schistosoma antigen, Entamoeba antigen, Streptococcus antigen, Mycobacteria antigen and PHA stimulated MIG release in CTRL and Mp-PAT. Notably, Entamoeba antigen and PHA strongly depressed (P < 0·0001) eotaxin-2 (CCL24) production in both study groups. Multiple regression analyses disclosed in Mp-PAT and CTRL dissimilar cellular chemokine and cytokine production levels being higher in Mp-PAT for CCL24, IL-27, IL-8, MCP-4, MDC and PARC (for all P < 0·0001), at baseline (P < 0·0001), in response to Entamoeba histolytica strain HM1 antigen (EhAg) (P < 0·0001), Onchocerca volvulus adult worm-derived antigen (OvAg) (P = 0·005), PHA (P < 0·0001) and purified protein derivative (PPD) (P < 0·0001) stimulation. In Mp-PAT with hookworm co-infection, the cellular chemokine production of CXCL10 (IP-10) was diminished. In summary, the chemokine and cytokine responses in Mp-PAT were in general not depressed, PBMC from Mp-PAT produced spontaneously and selectively inducible inflammatory and regulatory chemokines and cytokines at higher levels than CTRL and such diverse and distinctive reactivity supports that patent M. perstans infection will not polarize innate and adaptive cellular immune responsiveness in patients.
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Affiliation(s)
- B Wangala
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo
| | - R G Gantin
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo.,Institute for Tropical Medicine, University Clinics of Tübingen, Tübingen, Germany
| | - P S Voßberg
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo.,Institute for Tropical Medicine, University Clinics of Tübingen, Tübingen, Germany
| | - A Vovor
- Centre Hospitalier Universitaire Sylvanus Olympio, Laboratory for Hematology, Université de Lomé, Togo
| | - W P Poutouli
- Faculté de Sciences, Université de Lomé, Lomé, Togo
| | - K Komlan
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo
| | - M Banla
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo.,Centre Hospitalier Universitaire Campus, Université de Lomé, Togo
| | - C Köhler
- Institute for Tropical Medicine, University Clinics of Tübingen, Tübingen, Germany
| | - P T Soboslay
- National Institute of Hygiene, Onchocerciasis Reference Laboratory, Sokodé, Togo.,Institute for Tropical Medicine, University Clinics of Tübingen, Tübingen, Germany
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