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Parrella P, Elikan AB, Snow JW. Pathogen- and host-directed pharmacologic strategies for control of Vairimorpha (Nosema) spp. infection in honey bees. J Eukaryot Microbiol 2024:e13026. [PMID: 38572630 DOI: 10.1111/jeu.13026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 03/07/2024] [Indexed: 04/05/2024]
Abstract
Microsporidia are obligate intracellular parasites of the Fungal Kingdom that cause widespread infections in nature, with important effects on invertebrates involved in food production systems. The two microsporidian species Vairimorpha (Nosema) ceranae (and the less common Vairimorpha (Nosema) apis) can cause individual disease in honey bees and contribute to colony collapse. The efficacy, safety, and availability of fumagillin, the only drug currently approved to treat microsporidia infection in bees, is uncertain. In this review, we will discuss some of the most promising alternative strategies for the mitigation of Vairimorpha spp. with an emphasis on infection by V. ceranae, now the dominant species infecting bees. We will focus on pharmacologic interventions where the mechanism of action is known and examine both pathogen-directed and host-directed approaches. As limiting toxicity to host cells has been especially emphasized in treating bees that are already facing numerous stressors, strategies that disrupt pathogen-specific targets may be especially advantageous. Therefore, efforts to increase the knowledge and tools for facilitating the discovery of such targets and pharmacologic agents directed against them should be prioritized.
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Affiliation(s)
- Parker Parrella
- Department of Biology, Barnard College, New York, New York, USA
| | | | - Jonathan W Snow
- Department of Biology, Barnard College, New York, New York, USA
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Paromomycin Reduces Vairimorpha (Nosema) ceranae Infection in Honey Bees but Perturbs Microbiome Levels and Midgut Cell Function. Microorganisms 2022; 10:microorganisms10061107. [PMID: 35744625 PMCID: PMC9231153 DOI: 10.3390/microorganisms10061107] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 02/04/2023] Open
Abstract
Paromomycin is a naturally occurring aminoglycoside antibiotic that has effects on both prokaryotic and eukaryotic microbes. However, previous reports have indicated that it has little effect on microsporidia, including Vairimorpha (Nosema) ceranae, in cell culture models. V. ceranae is one of a number of microsporidia species that cause disease in honey bees and substantial efforts to find new treatment strategies for bees that are infected with these pathogens are ongoing. When testing compounds for potential activity against V. ceranae in whole organisms, we found that paromomycin reduces the infection intensity of this parasite. Critically, the necessary doses of paromomycin have high activity against the bacteria of the honey bee microbiome and cause evident stress in bees. Microsporidia have been shown to lack an essential binding site on the ribosome that is known to allow for maximal inhibition by paromomycin. Thus, it is possible that paromomycin impacts parasite levels through non-cell autonomous effects on microsporidia infection levels via effects on the microbiome or midgut cellular function. As paromomycin treatment could cause widespread honey bee health issues in agricultural settings, it does not represent an appropriate anti-microsporidia agent for use in the field.
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Wei J, Fei Z, Pan G, Weiss LM, Zhou Z. Current Therapy and Therapeutic Targets for Microsporidiosis. Front Microbiol 2022; 13:835390. [PMID: 35356517 PMCID: PMC8959712 DOI: 10.3389/fmicb.2022.835390] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/14/2022] [Indexed: 11/13/2022] Open
Abstract
Microsporidia are obligate intracellular, spore-forming parasitic fungi which are grouped with the Cryptomycota. They are both opportunistic pathogens in humans and emerging veterinary pathogens. In humans, they cause chronic diarrhea in immune-compromised patients and infection is associated with increased mortality. Besides their role in pébrine in sericulture, which was described in 1865, the prevalence and severity of microsporidiosis in beekeeping and aquaculture has increased markedly in recent decades. Therapy for these pathogens in medicine, veterinary, and agriculture has become a recent focus of attention. Currently, there are only a few commercially available antimicrosporidial drugs. New therapeutic agents are needed for these infections and this is an active area of investigation. In this article we provide a comprehensive summary of the current as well as several promising new agents for the treatment of microsporidiosis including: albendazole, fumagillin, nikkomycin, orlistat, synthetic polyamines, and quinolones. Therapeutic targets which could be utilized for the design of new drugs are also discussed including: tubulin, type 2 methionine aminopeptidase, polyamines, chitin synthases, topoisomerase IV, triosephosphate isomerase, and lipase. We also summarize reports on the utility of complementary and alternative medicine strategies including herbal extracts, propolis, and probiotics. This review should help facilitate drug development for combating microsporidiosis.
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Affiliation(s)
- Junhong Wei
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Key Laboratory for Sericulture Functional Genomics Biotechnology of Agricultural Ministry, Southwest University, Chongqing, China
| | - Zhihui Fei
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Key Laboratory for Sericulture Functional Genomics Biotechnology of Agricultural Ministry, Southwest University, Chongqing, China
| | - Guoqing Pan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Key Laboratory for Sericulture Functional Genomics Biotechnology of Agricultural Ministry, Southwest University, Chongqing, China
| | - Louis M. Weiss
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Zeyang Zhou
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
- Key Laboratory for Sericulture Functional Genomics Biotechnology of Agricultural Ministry, Southwest University, Chongqing, China
- College of Life Sciences, Chongqing Normal University, Chongqing, China
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Dual Molecular Diagnosis of Microsporidia (Encephalitozoon hellem) Keratoconjunctivitis in an Immunocompetent Adult. Cornea 2021; 40:242-244. [PMID: 32826651 DOI: 10.1097/ico.0000000000002466] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/13/2020] [Indexed: 11/25/2022]
Abstract
PURPOSE To report a case of microsporidia (Encephalitozoon hellem) keratoconjunctivitis acquired through avian transmission in an immunocompetent adult, diagnosed by metagenomic deep sequencing (MDS), and confirmed by polymerase chain reaction. METHODS A case report. RESULTS An 18-year-old woman was referred with unilateral keratoconjunctivitis unresponsive to topical and systemic therapy after exposure to birdcage debris. Slit-lamp examination of the left eye revealed a follicular papillary reaction of the palpebral conjunctiva and multiple corneal punctate epithelial opacities that stained minimally with fluorescein. In vivo confocal microscopy revealed bright double-walled structures and smaller bright round structures in the superficial epithelial debris and epithelium. Molecular diagnosis with MDS of E. hellem was confirmed by polymerase chain reaction. Clinical resolution and normalization of in vivo confocal microscopy was observed after a 6-week course of topical azithromycin. The patient elected a 3-week course of topical voriconazole 1% for definitive antimicrosporidial treatment, with no evidence of persistent infection 1 month later. CONCLUSIONS Microsporidial (E. hellem) keratoconjunctivitis can occur through avian transmission in immunocompetent hosts. Topical azithromycin may be effective against this pathogen. MDS has utility in the diagnosis of atypical keratoconjunctivitis.
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Birckhead A, Combs M, Croser E, Montgomery A, Peters A, Stark D, Malik R. Presumptive neural microsporidiosis in a young adult German Shepherd dog from rural Australia. Aust Vet J 2021; 99:351-355. [PMID: 33904161 DOI: 10.1111/avj.13071] [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: 12/06/2020] [Revised: 02/21/2021] [Accepted: 03/27/2021] [Indexed: 11/29/2022]
Abstract
CASE REPORT A 1-year-old, neutered male German Shepherd was presented with a 5-month history of episodic lethargy, intermittent fever, weight loss and a hunched posture. The dog was diagnosed with presumptive microsporidian meningoencephalitis based on cytological findings on cerebrospinal fluid analysis and a positive PCR test. The dog initially responded favourably to a 4-week course of trimethoprim-sulfadiazine, pyrimethamine and fenbendazole, and remained well for 12 weeks following cessation of treatment. Disease then recurred, and despite an initial positive response to treatment, he deteriorated and was euthanased 11 weeks later, 7.5 months after definitive diagnosis and 13 months after clinical signs were first reported. CONCLUSION To the authors knowledge, this is the first case of canine microsporidiosis in Australia.
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Affiliation(s)
- A Birckhead
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
| | - M Combs
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
| | - E Croser
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
| | - A Montgomery
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
| | - A Peters
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
| | - D Stark
- Microbiology Department, St Vincent's Hospital, Sydney, New South Wales, 2010, Australia
| | - R Malik
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia.,Centre for Veterinary Education, University of Sydney, Sydney, New South Wales, 2006, Australia
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Fingerhut A, Vargas-Caporali J, Leyva-Ramírez MA, Juaristi E, Tsogoeva SB. Biomimetic Non-Heme Iron-Catalyzed Epoxidation of Challenging Terminal Alkenes Using Aqueous H2O2 as an Environmentally Friendly Oxidant. Molecules 2019; 24:molecules24173182. [PMID: 31480640 PMCID: PMC6749192 DOI: 10.3390/molecules24173182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/20/2019] [Accepted: 08/23/2019] [Indexed: 11/21/2022] Open
Abstract
Catalysis mediated by iron complexes is emerging as an eco-friendly and inexpensive option in comparison to traditional metal catalysis. The epoxidation of alkenes constitutes an attractive application of iron(III) catalysis, in which terminal olefins are challenging substrates. Herein, we describe our study on the design of biomimetic non-heme ligands for the in situ generation of iron(III) complexes and their evaluation as potential catalysts in epoxidation of terminal olefins. Since it is well-known that active sites of oxidases might involve imidazole fragment of histidine, various simple imidazole derivatives (seven compounds) were initially evaluated in order to find the best reaction conditions and to develop, subsequently, more elaborated amino acid-derived peptide-like chiral ligands (10 derivatives) for enantioselective epoxidations.
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Affiliation(s)
- Anja Fingerhut
- Department of Chemistry and Pharmacy, Institute of Organic Chemistry I and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany
| | - Jorge Vargas-Caporali
- Department of Chemistry, Centro de Investigación y de Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, 07360 Ciudad de México, Mexico
| | - Marco Antonio Leyva-Ramírez
- Department of Chemistry, Centro de Investigación y de Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, 07360 Ciudad de México, Mexico
| | - Eusebio Juaristi
- Department of Chemistry, Centro de Investigación y de Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, 07360 Ciudad de México, Mexico.
- El Colegio Nacional, Donceles # 104, Centro Histórico, 06020 Ciudad de México, Mexico.
| | - Svetlana B Tsogoeva
- Department of Chemistry and Pharmacy, Institute of Organic Chemistry I and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany.
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Künzel F, Fisher PG. Clinical Signs, Diagnosis, and Treatment of Encephalitozoon cuniculi Infection in Rabbits. Vet Clin North Am Exot Anim Pract 2018; 21:69-82. [PMID: 29146032 DOI: 10.1016/j.cvex.2017.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Central vestibular dysfunction caused by Encephalitozoon cuniculi frequently mimics the condition of a peripheral disorder. A negative antibody titer rules out E cuniculi as the cause of present clinical signs. Cerebrospinal fluid analysis including polymerase chain reaction is considered an inappropriate diagnostic method for in vivo diagnosis of encephalitozoonosis. The usefulness of glucocorticoid anti-inflammatories in the treatment of encephalitozoonosis is called into question. Encouraging activity early in the course of disease and adding in therapeutic exercise may represent the most important part of therapy in rabbits with vestibular dysfunction associated with encephalitozoonosis.
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Affiliation(s)
- Frank Künzel
- Clinical Department of Small Animals and Horses, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria.
| | - Peter G Fisher
- Pet Care Veterinary Hospital, 5201 Virginia Beach Boulevard, Virginia Beach, VA 23462, USA
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Boileau M, Ferreira J, Ahmad I, Lavallée C, Qvarnstrom Y, Dufresne SF. Successful Treatment of Disseminated Anncaliia algerae Microsporidial Infection With Combination Fumagillin and Albendazole. Open Forum Infect Dis 2016; 3:ofw158. [PMID: 27704013 PMCID: PMC5047403 DOI: 10.1093/ofid/ofw158] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/19/2016] [Indexed: 11/23/2022] Open
Abstract
Anncaliia algerae myositis is a life-threatening, emerging microsporidiosis among immunocompromised hosts. We report a case of disseminated A algerae infection in a man previously treated with alemtuzumab. Due to failure of albendazole-based therapy, fumagillin was added as a novel approach to management, with a good clinical response and patient survival.
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Affiliation(s)
| | | | | | - Christian Lavallée
- Infectious Diseases and Medical Microbiology , Hôpital Maisonneuve-Rosemont, Université de Montréal , Canada
| | - Yvonne Qvarnstrom
- Division of Parasitic Diseases and Malaria , Centers for Disease Control and Prevention , Atlanta, Georgia
| | - Simon F Dufresne
- Infectious Diseases and Medical Microbiology , Hôpital Maisonneuve-Rosemont, Université de Montréal , Canada
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Dia N, Lavie L, Faye N, Méténier G, Yeramian E, Duroure C, Toguebaye BS, Frutos R, Niang MN, Vivarès CP, Ben Mamoun C, Cornillot E. Subtelomere organization in the genome of the microsporidian Encephalitozoon cuniculi: patterns of repeated sequences and physicochemical signatures. BMC Genomics 2016; 17:34. [PMID: 26744270 PMCID: PMC4704409 DOI: 10.1186/s12864-015-1920-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 09/11/2015] [Indexed: 12/23/2022] Open
Abstract
Background The microsporidian Encephalitozoon cuniculi is an obligate intracellular eukaryotic pathogen with a small nuclear genome (2.9 Mbp) consisting of 11 chromosomes. Although each chromosome end is known to contain a single rDNA unit, the incomplete assembly of subtelomeric regions following sequencing of the genome identified only 3 of the 22 expected rDNA units. While chromosome end assembly remains a difficult process in most eukaryotic genomes, it is of significant importance for pathogens because these regions encode factors important for virulence and host evasion. Results Here we report the first complete assembly of E. cuniculi chromosome ends, and describe a novel mosaic structure of segmental duplications (EXT repeats) in these regions. EXT repeats range in size between 3.5 and 23.8 kbp and contain four multigene families encoding membrane associated proteins. Twenty-one recombination sites were identified in the sub-terminal region of E. cuniculi chromosomes. Our analysis suggests that these sites contribute to the diversity of chromosome ends organization through Double Strand Break repair mechanisms. The region containing EXT repeats at chromosome extremities can be differentiated based on gene composition, GC content, recombination sites density and chromosome landscape. Conclusion Together this study provides the complete structure of the chromosome ends of E. cuniculi GB-M1, and identifies important factors, which could play a major role in parasite diversity and host-parasite interactions. Comparison with other eukaryotic genomes suggests that terminal regions could be distinguished precisely based on gene content, genetic instability and base composition biais. The diversity of processes assciated with chromosome extremities and their biological consequences, as they are presented in the present study, emphasize the fact that great effort will be necessary in the future to characterize more carefully these regions during whole genome sequencing efforts. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1920-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ndongo Dia
- Unité de Virologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, B.P. 220, Dakar, Sénégal.
| | - Laurence Lavie
- Clermont Université, Université Blaise Pascal, Laboratoire Microorganismes, Génome et Environnement, UMR 6023, CNRS, 63177, Aubière, France.
| | - Ngor Faye
- Laboratoire de Parasitologie Générale, Département de Biologie Animale, Faculté des Sciences et Technologies, Université Cheikh Anta Diop, Dakar, Sénégal.
| | - Guy Méténier
- Clermont Université, Université Blaise Pascal, Laboratoire Microorganismes, Génome et Environnement, UMR 6023, CNRS, 63177, Aubière, France.
| | - Edouard Yeramian
- Unité de Bioinformatique Structurale, UMR 3528 CNRS, Institut Pasteur, 25-28, rue du Dr Roux, 75015, Paris, France.
| | - Christophe Duroure
- Laboratoire de Météorologie Physique, OPGC UMR 6016 CNRS-Université Blaise Pascal, 24 Avenue des Landais, 63177, Aubière Cedex, France.
| | - Bhen S Toguebaye
- Laboratoire de Parasitologie Générale, Département de Biologie Animale, Faculté des Sciences et Technologies, Université Cheikh Anta Diop, Dakar, Sénégal.
| | - Roger Frutos
- CIRAD, UMR 17, Cirad-Ird, TA-A17/G, Campus International de Baillarguet, 34398, Montpellier, France.
| | - Mbayame N Niang
- Unité de Virologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, B.P. 220, Dakar, Sénégal.
| | - Christian P Vivarès
- Clermont Université, Université Blaise Pascal, Laboratoire Microorganismes, Génome et Environnement, UMR 6023, CNRS, 63177, Aubière, France.
| | - Choukri Ben Mamoun
- Section of Infectious Disease and Department of Microbial Pathogenesis, Winchester Building WWW403D, Yale School of Medicine, 15 York St., New Haven, CT, 06520, USA.
| | - Emmanuel Cornillot
- Institut de Recherche en Cancérologie de Montpellier, IRCM - INSERM U1194 & Université de Montpellier & ICM, Institut régional du Cancer Montpellier, Campus Val d'Aurelle, 34298, Montpellier cedex 5, France. .,Institut de Biologie Computationnelle, IBC, Campus Saint Priest, 34090, Montpellier, France.
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Abu-Akkada SS, Oda SS. Prevention and treatment of Encephalitozoon cuniculi infection in immunosuppressed rabbits with fenbendazole. IRANIAN JOURNAL OF VETERINARY RESEARCH 2016; 17:98-105. [PMID: 27822234 PMCID: PMC5090138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Revised: 01/16/2016] [Accepted: 01/20/2016] [Indexed: 06/06/2023]
Abstract
This study was conducted to evaluate the efficacy of oral administration of fenbendazole (20 mg/kg body weight) prior to and after experimental infection of immunosuppressed rabbits with Encephalitozoon cuniculi. A total of thirty rabbits were divided into five groups: NN (non-immunosuppressed; non-infected), IN (immunosuppressed; non-infected), IPI (immunosuppressed; protected-infected), ITI (immunosuppressed; treated-infected), and II (immunosuppressed; infected) groups. Fenbendazole was administered as a prophylactic for seven successive days before infection with E. cuniculi and as a treatment for four weeks initiated on the 28th day post-challenge (PC). Experimental rabbits were infected with intraperitoneal injection of 2 × 105E. cuniculi spores. Parameters evaluated were body weight, detection of spores in urine, serum antibody assay, hematological, biochemical and histopathological changes. The IPI and ITI groups showed a significant better final bwt than the II group. Spores were detected in urine of all infected rabbits from the 28th day PC until the end of the study. The IPI group showed the least values of antibodies (IgG) compared to the ITI and II groups. Concerning histopathological changes, the intensity of the lesions was marked particularly in the II rabbits and to a lesser extent in the ITI rabbits. Noticeable improvement was found in the IPI rabbits. It could be concluded that fenbendazole was effective to some extent in protection of rabbits against E. cuniculi infection, while when administered as a therapeutic no significant effects were observed.
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Affiliation(s)
- S. S. Abu-Akkada
- Department of Parasitology, Faculty of Veterinary Medicine, Alexandria University, Edfina, Behera, Egypt
| | - S. S. Oda
- Department of Pathology, Faculty of Veterinary Medicine, Alexandria University, Edfina, Behera, Egypt
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11
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Microsporidiosis in Vertebrate Companion Exotic Animals. J Fungi (Basel) 2015; 2:jof2010003. [PMID: 29376921 PMCID: PMC5753084 DOI: 10.3390/jof2010003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 12/07/2015] [Accepted: 12/18/2015] [Indexed: 11/17/2022] Open
Abstract
Veterinarians caring for companion animals may encounter microsporidia in various host species, and diagnosis and treatment of these fungal organisms can be particularly challenging. Fourteen microsporidial species have been reported to infect humans and some of them are zoonotic; however, to date, direct zoonotic transmission is difficult to document versus transit through the digestive tract. In this context, summarizing information available about microsporidiosis of companion exotic animals is relevant due to the proximity of these animals to their owners. Diagnostic modalities and therapeutic challenges are reviewed by taxa. Further studies are needed to better assess risks associated with animal microsporidia for immunosuppressed owners and to improve detection and treatment of infected companion animals.
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12
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Gisder S, Genersch E. Identification of candidate agents active against N. ceranae infection in honey bees: establishment of a medium throughput screening assay based on N. ceranae infected cultured cells. PLoS One 2015; 10:e0117200. [PMID: 25658121 PMCID: PMC4320070 DOI: 10.1371/journal.pone.0117200] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/20/2014] [Indexed: 11/18/2022] Open
Abstract
Many flowering plants in both natural ecosytems and agriculture are dependent on insect pollination for fruit set and seed production. Managed honey bees (Apis mellifera) and wild bees are key pollinators providing this indispensable eco- and agrosystem service. Like all other organisms, bees are attacked by numerous pathogens and parasites. Nosema apis is a honey bee pathogenic microsporidium which is widely distributed in honey bee populations without causing much harm. Its congener Nosema ceranae was originally described as pathogen of the Eastern honey bee (Apis cerana) but jumped host from A. cerana to A. mellifera about 20 years ago and spilled over from A. mellifera to Bombus spp. quite recently. N. ceranae is now considered a deadly emerging parasite of both Western honey bees and bumblebees. Hence, novel and sustainable treatment strategies against N. ceranae are urgently needed to protect honey and wild bees. We here present the development of an in vitro medium throughput screening assay for the identification of candidate agents active against N. ceranae infections. This novel assay is based on our recently developed cell culture model for N. ceranae and coupled with an RT-PCR-ELISA protocol for quantification of N. ceranae in infected cells. The assay has been adapted to the 96-well microplate format to allow automated analysis. Several substances with known (fumagillin) or presumed (surfactin) or no (paromomycin) activity against N. ceranae were tested as well as substances for which no data concerning N. ceranae inhibition existed. While fumagillin and two nitroimidazoles (metronidazole, tinidazole) totally inhibited N. ceranae proliferation, all other test substances were inactive. In summary, the assay proved suitable for substance screening and demonstrated the activity of two synthetic antibiotics against N. ceranae.
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Affiliation(s)
- Sebastian Gisder
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Elke Genersch
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
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13
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Saleh M, Kumar G, Abdel-Baki AA, Dkhil M, El-Matbouli M, Al-Quraishy S. Development of a novel in vitro method for drug development for fish; application to test efficacy of antimicrosporidian compounds. Vet Rec 2014; 175:561. [PMID: 25200429 DOI: 10.1136/vr.102604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Few drugs are approved for treating diseases caused by parasites in minor species such as fish. This is due, in part, to the expense of drug development and to the comparatively small market. In vivo effectiveness trials for antiparasitic drugs are costly, time consuming and require ethics approval, therefore an in vitro screening approach is a cost-effective alternative to finding promising drug candidates. We developed an in vitro testing system to test antimicrosporidial compounds against a microsporidian pathogen Heterosporis saurida. Five antiparasitic compounds, albendazole, fumagillin, TNP-70, nitazoxanide and lufenuron, were assayed for antimicrosporidial activity. All compounds reduced the number of H saurida spores in infected cells when applied at a concentration that did not appear to be toxic to the host cells. Albendazole inhibited replication of H saurida by >60 per cent, fumagillin and its analogue TNP-470 inhibited H saurida >80 per cent, nitazoxanide and lufenuron inhibited growth >70 per cent. The data suggest that both fumagillin and its analogous TNP-70 hold the best promise as therapeutic agents against H saurida. The ability to use fish cell cultures to assess drugs against H saurida demonstrates an approach that may be helpful to evaluate other drugs on different microsporidia and host cells.
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Affiliation(s)
- M Saleh
- Clinical Division of Fish Medicine, University of Veterinary Medicine, Vienna, Austria
| | - G Kumar
- Clinical Division of Fish Medicine, University of Veterinary Medicine, Vienna, Austria
| | - A-A Abdel-Baki
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia Faculty of Science, Zoology Department, Beni-Suef University, Beni-Suef, Egypt
| | - M Dkhil
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia Faculty of Science, Department of Zoology and Entomology, Helwan University, Cairo, Egypt
| | - M El-Matbouli
- Clinical Division of Fish Medicine, University of Veterinary Medicine, Vienna, Austria
| | - S Al-Quraishy
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
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14
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Watts MR, Chan RCF, Cheong EYL, Brammah S, Clezy KR, Tong C, Marriott D, Webb CE, Chacko B, Tobias V, Outhred AC, Field AS, Prowse MV, Bertouch JV, Stark D, Reddel SW. Anncaliia algerae microsporidial myositis. Emerg Infect Dis 2014; 20:185-91. [PMID: 24447398 PMCID: PMC3901472 DOI: 10.3201/eid2002.131126] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The insect microsporidian Anncaliia algerae was first described in 2004 as a cause of fatal myositis in an immunosuppressed person from Pennsylvania, USA. Two cases were subsequently reported, and we detail 2 additional cases, including the only nonfatal case. We reviewed all 5 case histories with respect to clinical characteristics, diagnosis, and management and summarized organism life cycle and epidemiology. Before infection, all case-patients were using immunosuppressive medications for rheumatoid arthritis or solid-organ transplantation. Four of the 5 case-patients were from Australia. All diagnoses were confirmed by skeletal muscle biopsy; however, peripheral nerves and other tissues may be infected. The surviving patient received albendazole and had a reduction of immunosuppressive medications and measures to prevent complications. Although insects are the natural hosts for A. algerae, human contact with water contaminated by spores may be a mode of transmission. A. algerae has emerged as a cause of myositis, particularly in coastal Australia.
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Effect of three drugs against Encephalitozoon cuniculi infection in immunosuppressed mice. Antimicrob Agents Chemother 2013; 57:3067-71. [PMID: 23612191 DOI: 10.1128/aac.00157-13] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Microsporidia comprise a large group of obligate intracellular parasites. The microsporidian Encephalitozoon cuniculi causes disseminated infection in immunosuppressed patients with HIV, cancer, or transplants and in the elderly. In vivo and in vitro studies on the effectiveness of drugs are controversial. Currently, there is no effective treatment. We tested albendazole, albendazole sulfoxide, metronidazole, and cyclosporine in mice immunosuppressed with cyclophosphamide and inoculated by the intraperitoneal route with 10(7) E. cuniculi spores. One week after experimental inoculation, the mice were treated with albendazole, albendazole sulfoxide, metronidazole, and cyclosporine. Histological and morphometric analyses were performed to compare the treated groups. The state of immunosuppression was evaluated by phenotyping CD4(+) and CD8(+) T cells by flow cytometry. Nontreated mice showed acute disseminated and fatal encephalitozoonosis. The treatment with benzimidazoles significantly reduced infection until 30 days posttreatment (p.t.), but at 60 days p.t., the infection had recurred. Metronidazole decreased infection by a short time, and cyclosporine was not effective. All animals were immunosuppressed by all the experiments, as demonstrated by the low number of CD4(+) and CD8(+) T cells. We conclude that no drug was effective against E. cuniculi, but the benzimidazoles controlled the infection transiently.
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Sieg J, Hein J, Jass A, Sauter-Louis C, Hartmann K, Fischer A. Clinical evaluation of therapeutic success in rabbits with suspected encephalitozoonosis. Vet Parasitol 2012; 187:328-32. [PMID: 22309799 DOI: 10.1016/j.vetpar.2011.12.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Revised: 12/04/2011] [Accepted: 12/16/2011] [Indexed: 11/16/2022]
Abstract
Between 2000 and 2008, 95 rabbits with suspected encephalitozoonosis and neurological symptoms were treated at the Clinic of Small Animal Medicine, Ludwig Maximilian University Munich. Standard treatment consisted of oxytetracycline (from 2000 to 2003; n=50) or fenbendazole and oxytetracycline (from 2004 to 2008; n=45), and the rabbits were randomly assigned to treatment groups with or without dexamethasone. Each therapeutic regime was given for 10 days, with fluids, B vitamins and nutritional support added as needed. Therapeutic success was evaluated by assessing the survival rate on day 10, the neurological score of the surviving rabbits and Kaplan-Meier curves for long-term survival past 10 days. Inclusion of fenbendazole in the treatment protocol was associated with increased survival rates on day 10 (p=0.043), better neurological scores (p=0.008), and improved long-term survival (p=0.025) based on the results of univariate analyses. Treatment with dexamethasone showed no effect on neurological score or on short- or long-term survival. The study did not provide any evidence that dexamethasone is an effective component of the treatment scheme.
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Affiliation(s)
- Jessica Sieg
- Clinic of Small Animal Medicine Department of Veterinary Clinical Sciences, Ludwig Maximilians University Munich, Veterinärstr. 13, 80539 Munich, Germany
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17
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Microsporidiosis: Epidemiology, clinical data and therapy. ACTA ACUST UNITED AC 2010; 34:450-64. [DOI: 10.1016/j.gcb.2010.07.003] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 06/22/2010] [Accepted: 07/05/2010] [Indexed: 11/19/2022]
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18
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Disseminated infection with a new genovar of Encephalitozoon cuniculi in a renal transplant recipient. J Clin Microbiol 2010; 48:2651-3. [PMID: 20463169 DOI: 10.1128/jcm.02539-09] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Disseminated microsporidiosis is a life-threatening opportunistic infection. Here, we report about a previously undescribed genovar of Encephalitozoon cuniculi causing disseminated infection in a non-HIV-infected renal transplant recipient. Disseminated microsporidiosis must be considered in the differential diagnosis of chronic fever in renal allograft recipients, even those without urinary symptoms.
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Abstract
Encephalitozoon cuniculi is an obligatory intracellular microsporidian parasite that can infect a wide range of mammals, including rodents, rabbits, horses, carnivores and humans, in which the organism is known as an opportunistic pathogen of immunocompromised individuals. Nevertheless, the main host for E. cuniculi is the rabbit and infections usually have a sub-clinical course. However, severe disease is recognised in pet rabbits more frequently within the last years. As the central nervous system, the kidney and the eye are predilection organs for the organism, predominant histopathological alterations comprise granulomatous meningoencephalitis, chronic interstitial nephritis and phacoclastic uveitis. A definitive diagnosis of encephalitozoonosis in vivo is difficult, but it is important for specific treatment and the determination of possible zoonotic risks. This review article covers epidemiology, pathology, pathophysiology, immunology, clinical signs, differential diagnosis, diagnosis and treatment of encephalitozoonosis in rabbits.
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20
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Monaghan SR, Kent ML, Watral VG, Kaufman RJ, Lee LEJ, Bols NC. Animal cell cultures in microsporidial research: their general roles and their specific use for fish microsporidia. In Vitro Cell Dev Biol Anim 2009; 45:135-47. [PMID: 19184249 PMCID: PMC4760642 DOI: 10.1007/s11626-008-9172-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Accepted: 12/20/2008] [Indexed: 10/21/2022]
Abstract
The use of animal cell cultures as tools for studying the microsporidia of insects and mammals is briefly reviewed, along with an in depth review of the literature on using fish cell cultures to study the microsporidia of fish. Fish cell cultures have been used less often but have had some success. Very short-term primary cultures have been used to show how microsporidia spores can modulate the activities of phagocytes. The most successful microsporidia/fish cell culture system has been relatively long-term primary cultures of salmonid leukocytes for culturing Nucleospora salmonis. Surprisingly, this system can also support the development of Enterocytozoon bienusi, which is of mammalian origin. Some modest success has been achieved in growing Pseudoloma neurophilia on several different fish cell lines. The eel cell line, EP-1, appears to be the only published example of any fish cell line being permanently infected with microsporidia, in this case Heterosporis anguillarum. These cell culture approaches promise to be valuable in understanding and treating microsporidia infections in fish, which are increasingly of economic importance.
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Affiliation(s)
- S Richelle Monaghan
- Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
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21
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Johny S, Whitman DW. Effect of four antimicrobials against an Encephalitozoon sp. (Microsporidia) in a grasshopper host. Parasitol Int 2008; 57:362-7. [PMID: 18495525 DOI: 10.1016/j.parint.2008.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 03/13/2008] [Accepted: 03/20/2008] [Indexed: 11/15/2022]
Abstract
Encephalitozoon spp. are the primary microsporidial pathogens of humans and domesticated animals. In this experiment, we test the efficacy of 4 commercial antimicrobials against an Encephalitozoon sp. infecting a grasshopper (Romalea microptera) host. Oral treatment with fumagillin or thiabendazole significantly reduced pathogen spore counts (93% and 88% respectively), whereas spore counts of grasshoppers fed quinine produced a non-significant 53% reduction in spores, and those fed streptomycin a non-significant 29% increase in spores, compared to the control. We observed a moderate dose-response effect for thiabendazole, whereby spore count decreased as drug consumption increased. No thiabendazole-treated animals died, whereas 27% of streptomycin-treated animals died, suggesting that thiabendazole was not toxic at the doses administered. The deaths among streptomycin-treated animals may have been caused by drug toxicity, parasite burden, or both. Although fumagillin and thiabendazole significantly reduced spore counts, in no individual was the pathogen totally eliminated. Our data confirm that microsporidia are difficult to control and that fumagillin and thiabendazole are partially effective antimicrobials against this group. Our study suggests that quinine and related alkaloids should be further examined for antimicrosporidial activity, and streptomycin should be examined as a possible enhancer of microsporidiosis.
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Affiliation(s)
- Shajahan Johny
- Department of Biological Sciences, Illinois State University, Normal, Illinois 61790-4120, USA
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22
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Johny S, Lange CE, Solter LF, Merisko A, Whitman DW. NEW INSECT SYSTEM FOR TESTING ANTIBIOTICS. J Parasitol 2007; 93:1505-11. [DOI: 10.1645/ge-1213.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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23
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Dia N, Lavie L, Méténier G, Toguebaye BS, Vivarès CP, Cornillot E. InterB multigenic family, a gene repertoire associated with subterminal chromosome regions of Encephalitozoon cuniculi and conserved in several human-infecting microsporidian species. Curr Genet 2007; 51:171-86. [PMID: 17235519 DOI: 10.1007/s00294-006-0114-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 11/08/2006] [Accepted: 11/28/2006] [Indexed: 11/30/2022]
Abstract
Microsporidia are fungi-related obligate intracellular parasites that infect numerous animals, including man. Encephalitozoon cuniculi harbours a very small genome (2.9 Mbp) with about 2,000 coding sequences (CDSs). Most repeated CDSs are of unknown function and are distributed in subterminal regions that mark the transitions between subtelomeric rDNA units and chromosome cores. A potential multigenic family (interB) encoding proteins within a size range of 579-641 aa was investigated by PCR and RT-PCR. Thirty members were finally assigned to the E. cuniculi interB family and a predominant interB transcript was found to originate from a newly identified gene on chromosome III. Microsporidian species from eight different genera infecting insects, fishes or mammals, were tested for a possible intra-phylum conservation of interB genes. Only representatives of the Encephalitozoon, Vittaforma and Brachiola genera, differing in host range but all able to invade humans, were positive. Molecular karyotyping of Brachiola algerae showed a complex set of chromosome bands, providing a haploid genome size estimate of 15-20 Mbp. In spite of this large difference in genome complexity, B. algerae and E. cuniculi shared some similar interB gene copies and a common location of interB genes in near-rDNA subterminal regions.
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Affiliation(s)
- Ndongo Dia
- Equipe Parasitologie Moléculaire et Cellulaire, Laboratoire de Biologie des Protistes, UMR CNRS 6023, Bâtiment Biologie A, Université Blaise Pascal, 63177 Aubière cedex, France
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24
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Didier ES, Maddry JA, Brindley PJ, Stovall ME, Didier PJ. Therapeutic strategies for human microsporidia infections. Expert Rev Anti Infect Ther 2007; 3:419-34. [PMID: 15954858 DOI: 10.1586/14787210.3.3.419] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Over the past 20 years, microsporidia have emerged as a cause of infectious diseases in AIDS patients, organ transplant recipients, children, travelers, contact lens wearers and the elderly. Enterocytozoon bieneusi and the Encephalitozoon spp., Encephalitozoon cuniculi, Encephalitozoon hellem and Encephalitozoon intestinalis, are the most frequently identified microsporidia in humans, and are associated with diarrhea and systemic disease. The microsporidia are small, single-celled, obligately intracellular parasites that have been identified in water sources, as well as in wild, domestic and food-producing farm animals, thereby raising concerns for waterborne, foodborne and zoonotic transmission. Current therapies for microsporidiosis include albendazole, a benzimidazole that inhibits microtubule assembly and is effective against several microsporidia, including the Encephalitozoon spp., although it is less effective against Encephalitozoon bieneusi. Fumagillin, an antibiotic and antiangiogenic compound produced by Aspergillus fumigatus, is more broadly effective against Encephalitozoon spp. and E. bieneusi; however, is toxic when administered systemically to mammals. Recent studies are also focusing on compounds that target the microsporidia polyamines (e.g., polyamine analogs), methionine aminopeptidase 2 (e.g., fumagillin-related compounds), chitin inhibitors (e.g., nikkomycins), topoisomerases (e.g., fluoroquinolones) and tubulin (e.g., benzimidazole-related compounds).
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Affiliation(s)
- Elizabeth S Didier
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
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25
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Taupin V, Méténier G, Vivarès CP, Prensier G. An improved procedure for Percoll gradient separation of sporogonial stages in Encephalitozoon cuniculi (Microsporidia). Parasitol Res 2006; 99:708-14. [PMID: 16738886 DOI: 10.1007/s00436-006-0231-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Accepted: 04/27/2006] [Indexed: 10/24/2022]
Abstract
Intracellular development of microsporidian parasites comprises a proliferative phase (merogony) followed by a differentiation phase (sporogony) leading to the release of resistant spores. Sporogony implies, successively, meront-to-sporont transformation, sporont division into sporoblasts, and sporogenesis. We report a procedure improving the separation of sporogonial stages of Encephalitozoon cuniculi, a species that develops inside parasitophorous vacuoles of mammalian cells. Supernatants of E. cuniculi-infected Madin-Darby canine kidney cell cultures provided a large number of parasites mixed with host-cell debris. This material was gently homogenized in phosphate-buffered saline containing 0.05% saponin and 0.05% Triton X-100 then filtered through glass wool columns. Centrifugation of the filtrate on 70% Percoll-0.23 M sucrose gradient gave a reproducible pattern of bands at different densities. Transmission electron microscopy showed that three of the four collected fractions were free of visible contaminants. Corresponding prominent cell stages were early sporoblasts (fraction B), late sporoblasts plus immature spores (fraction C), and mature spores (fraction D). Further centrifugation of the lightest fraction (A) on 30% Percoll-0.23 M sucrose gradient generated a sporont-rich fraction (A2). First analysis of proteins from fractions A2 and D by two-dimensional gel electrophoresis suggested a potential use of the described method for proteomic profiling.
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Affiliation(s)
- Vanessa Taupin
- Equipe Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière Cedex, France
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27
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Franzen C, Müller A, Hartmann P, Salzberger B. Quantitation of microsporidia in cultured cells by flow cytometry. Cytometry A 2005; 60:107-14. [PMID: 15229863 DOI: 10.1002/cyto.a.20028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Microsporidia are obligate intracellular protozoan parasites that emerged as major opportunistic pathogens in humans since the onset of the AIDS pandemic. In the present study, we investigated whether FCM is a useful method for the quantitation of intracellular microsporidian spores in cultured cells. METHODS Microsporidia (Encephalitozoon cuniculi) were grown in cell cultures and various cell-lines were coincubated with microsporidian spores at different multiplicities of infection, as well as for different periods of time. After permeabilization of the cells, intracellular spores were stained with a polyclonal anti-E. cuniculi serum and a FITC-labeled secondary antibody. Stained cells were analyzed on a flow cytometer and results were compared with those of fluorescence microscopy. RESULTS Noninfected cells showed a lower fluorescence, while the relative fluorescence observed for infected cells was significantly higher. The cell population with the more intense fluorescence, representing cells with internalized microsporidian spores, increased with the multiplicity of infection as well as over time. Results of FCM and fluorescence microscopy were in excellent agreement for all experiments. CONCLUSIONS We have developed a flow cytometric assay to detect and quantify cells with intracellular microsporidian spores. This method is easy to use, highly reproducible, and should be useful for future research.
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Affiliation(s)
- Caspar Franzen
- Department of Internal Medicine I, University of Regensburg, Regensburg, Germany.
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28
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Brugere JF, Cornillot E, Bourbon T, Metenier G, Vivarès CP. Inter-strain variability of insertion/deletion events in the Encephalitozoon cuniculi genome: a comparative KARD-PFGE analysis. J Eukaryot Microbiol 2002; Suppl:50S-55S. [PMID: 11906078 DOI: 10.1111/j.1550-7408.2001.tb00451.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We applied a two-dimensional pulsed-field gel electrophoresis procedure to the genomes of two karyotype variants assigned to two different strains of the microsporidian Encephalitozoon cuniculi, termed D (strain III) and F (strain II). Data obtained for BssHII and MluI restriction fragment length polymorphisms in each chromosome are compiled and compared to the reference strain I variant A. Six Insertion/Deletion (InDels) are found in subterminal position, some of these being characteristic of either D or F. Like in strain 1, the terminal fragments extending between each telomere and rDNA locus are conserved in length for each chromosome. They are however smaller than in reference variant. This size reduction is estimated to be 2.5 kbp for the strain III isolate and 3.5 kbp for the strain II isolate. We hypothesize that for the three E. cuniculi strains, all chromosome extremities are prone to a constant process of sequence homogenization through mitotic recombination between conserved regions.
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Affiliation(s)
- J F Brugere
- Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, Aubière, France
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29
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Millership JJ, Didier ES, Okhuysen PC, Maddry JA, Kwong CD, Chen X, Snowden KF. In vitro and in vivo evaluation of aminopeptidase inhibitors as antimicrosporidial therapies. J Eukaryot Microbiol 2002; Suppl:95S-98S. [PMID: 11906096 DOI: 10.1111/j.1550-7408.2001.tb00468.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J J Millership
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, USA
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30
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Molina JM, Tourneur M, Sarfati C, Chevret S, de Gouvello A, Gobert JG, Balkan S, Derouin F. Fumagillin treatment of intestinal microsporidiosis. N Engl J Med 2002; 346:1963-9. [PMID: 12075057 DOI: 10.1056/nejmoa012924] [Citation(s) in RCA: 200] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Intestinal microsporidiosis due to Enterocytozoon bieneusi is a cause of chronic diarrhea, malabsorption, and wasting in immunocompromised patients. Currently, there is no effective treatment. METHODS We conducted a randomized, double-blind, placebo-controlled trial of fumagillin (60 mg per day orally for two weeks) in patients with chronic E. bieneusi infection. Efficacy was assessed primarily by the clearance of microsporidia, as evidenced by analysis of stool specimens. Patients in whom microsporidia were not cleared received treatment for two weeks with open-label fumagillin. After clearance of the parasite, follow-up stool examinations were performed monthly to detect relapses. RESULTS Twelve patients were enrolled in this study, 10 with the acquired immunodeficiency syndrome and 2 who had received organ transplants. Clearance of microsporidia occurred in all six of the patients in the fumagillin group, as compared with none of the six in the placebo group (P=0.002). Treatment with fumagillin was also associated with increases in absorption of D-xylose (P=0.003) and in Karnofsky performance scores (P<0.001) and with decreases in loperamide use (P=0.01) and total stool weight (P=0.04). There were serious adverse events (neutropenia and thrombocytopenia) in three patients in the fumagillin group; one patient in the placebo group had severe diarrhea. All six controls subsequently had clearance of microsporidia after open-label treatment with fumagillin. Relapses of the infection were identified in two patients during follow-up (median follow-up, 10 months). CONCLUSIONS Fumagillin is an effective treatment for chronic E. bieneusi infection in immunocompromised patients.
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Affiliation(s)
- Jean-Michel Molina
- Department of Infectious Diseases, Hôpital Saint-Louis and University of Paris VII, Paris, France.
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31
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Lafranchi-Tristem NJ, Curry A, Cheney SA, Canning EU. Growth of Trachipleistophora hominis (Microsporidia: Pleistophoridae) in C2,C12 mouse myoblast cells and response to treatment with albendazole. Folia Parasitol (Praha) 2002; 48:192-200. [PMID: 11699654 DOI: 10.14411/fp.2001.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The microsporidium Trachipleistophora hominis Hollister, Canning, Weidner, Field, Kench et Marriott, 1996, originally isolated from human skeletal muscle cells, inhibited myotube formation from myoblasts when grown in a mouse myoblast cell line C2,C12. Uninfected cultures readily converted to myotubes. Albendazole, a drug with known antimicrosporidial activity, was tested against T. hominis in C2,C12 cells. The drug was added when infection had reached 75% of C2,C12 cells, a level comparable to that obtained in heavily infected muscle in vivo. Doses of 1 ng/ml and 10 ng/ml had no effect on merogony or sporogony. In cultures exposed to 100 ng/ml albendazole, the C2,C12 cells remained in good condition while infection levels dropped to 25% over 7 weeks. Drug doses of 500 ng/ml and 1,000 ng/ml were deleterious to the host cells but some spores retained viability and were able to establish new infections once albendazole pressure was removed. T. hominis meronts exposed to 100 ng/ml albendazole mostly lacked the normally thick surface coat and its reticulate extensions. Meronts were not seen in cultures exposed to higher drug doses. Albendazole at a concentration of 100 ng/ml and higher had a profound effect on spore morphogenesis. There was erratic coiling of the polar tube, often involving the formation of double tubes, and chaotic disposition of membranes which could have been those of polaroplast. The in vitro susceptibility of T. hominis to albendazole was low in comparison with in vitro susceptibility of other microsporidia of human origin.
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Affiliation(s)
- N J Lafranchi-Tristem
- Department of Biology, Imperial College of Science, Technology and Medicine, London, UK
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El Alaoui H, Bata J, Peyret P, Vivarès CP. Encephalitozoon cuniculi (Microspora): characterization of a phospholipid metabolic pathway potentially linked to therapeutics. Exp Parasitol 2001; 98:171-9. [PMID: 11560410 DOI: 10.1006/expr.2001.4635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipid metabolism of the microsporidian Encephalitozoon cuniculi, an obligate intracellular parasite, has been investigated. Labeled precursor incorporation experiments have shown that phosphatidylserine decarboxylase and phosphatidylethanolamine N-methyltransferase are more active in cells infected by E. cuniculi than in uninfected cells. In contrast, no difference was observed in the activity of Kennedy pathway's enzymes, the mammalian pathway. This suggests the occurrence in microsporidia of a bacteria- and fungi-typical pathway for phospholipid synthesis, which is supported by the identification of two genes implicated in this pathway, the cds gene encoding the key enzyme CDP-diacylglycerol synthase (E.C. 2.7.7.41) and the pss gene for CDP-alcohol phosphatidyltransferase. The pss gene could encode phosphatidylserine synthase (E.C. 2.7.8.8.), which catalyses the de novo synthesis of phosphatidylserine in bacteria and fungi. The complete CDP-diacylglycerol synthase messenger has been isolated and shows very short 5' and 3' untranslated regions. This is strong evidence for the functionality of a metabolic pathway which could be a potential target against microsporidia which infect humans.
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Affiliation(s)
- H El Alaoui
- Laboratoire de Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Biologie A, 63177 Aubière Cedex, France
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Peyret P, Katinka MD, Duprat S, Duffieux F, Barbe V, Barbazanges M, Weissenbach J, Saurin W, Vivarès CP. Sequence and analysis of chromosome I of the amitochondriate intracellular parasite Encephalitozoon cuniculi (Microspora). Genome Res 2001; 11:198-207. [PMID: 11157783 PMCID: PMC311017 DOI: 10.1101/gr.164301] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A DNA sequencing program was applied to the small (<3 Mb) genome of the microsporidian Encephalitozoon cuniculi, an amitochondriate eukaryotic parasite of mammals, and the sequence of the smallest chromosome was determined. The approximately 224-kb E. cuniculi chromosome I exhibits a dyad symmetry characterized by two identical 37-kb subtelomeric regions which are divergently oriented and extend just downstream of the inverted copies of an 8-kb duplicated cluster of six genes. Each subtelomeric region comprises a single 16S-23S rDNA transcription unit, flanked by various tandemly repeated sequences, and ends with approximately 1 kb of heterogeneous telomeric repeats. The central (or core) region of the chromosome harbors a highly compact arrangement of 132 potential protein-coding genes plus two tRNA genes (one gene per 1.14 kb). Most genes occur as single copies with no identified introns. Of these putative genes, only 53 could be assigned to known functions. A number of genes from the transcription and translation machineries as well as from other cellular processes display characteristic eukaryotic signatures or are clearly eukaryote-specific.
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Affiliation(s)
- P Peyret
- Equipe de Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, 63177 Aubière Cedex, France. pierre.peyret@ lbp.univ-bpclermont.fr
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Delbac F, Peuvel I, Metenier G, Peyretaillade E, Vivares CP. Microsporidian invasion apparatus: identification of a novel polar tube protein and evidence for clustering of ptp1 and ptp2 genes in three Encephalitozoon species. Infect Immun 2001; 69:1016-24. [PMID: 11159998 PMCID: PMC97982 DOI: 10.1128/iai.69.2.1016-1024.2001] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia are unicellular eukaryotes occurring as obligate intracellular parasites which produce resistant spores. A unique motile process is represented by the sudden extrusion of the sporal polar tube for initiating entry of the parasite into a new host cell. The complete sequence of an acidic proline-rich polar tube protein (renamed PTP1) has been previously reported for Encephalitozoon cuniculi and E. hellem. Our immunological investigations provided evidence for an additional PTP in E. cuniculi, termed PTP2. The corresponding gene was sequenced and then expressed in Escherichia coli. As expected, mouse antibodies raised against the recombinant protein reacted specifically with the polar tube. The single copy ptp1 and ptp2 genes of E. cuniculi were tandemly arranged on chromosome VI. Polyadenylation of the mRNAs was demonstrated. Identification and sequencing of homologous genes in the two other human-infecting Encephalitozoon species (ptp2 in E. hellem and ptp1 and ptp2 in E. intestinalis) were facilitated by conserved gene clustering. PTP2 appears as a novel structural protein (30 kDa) with a basic lysine-rich core and an acidic tail. Unlike PTP1, this protein is devoid of large tandem repeats. The interspecies conservation of cysteine residues supports a major role of disulfide bridges in polar tube assembly. The two PTPs should serve as both molecular markers of spore differentiation and diagnostic tools.
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Affiliation(s)
- F Delbac
- Equipe de Parasitologie Moleculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, 63177 Aubière Cedex, France.
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Abstract
Microsporidia are ubiquitous organisms that are emerging pathogens in humans. These are most likely zoonotic and/or waterborne infections. In the immunosuppressed host, such as those treated with immunosuppressive drugs or infected with human immunodeficiency virus particularly at advanced stages of the disease, microsporidia can produce a wide range of clinical diseases. The most common manifestation is gastrointestinal tract infection; however, encephalitis, ocular infection, sinusitis, myositis and disseminated infection have also been described. In addition, these organisms have been reported in immune competent individuals. Multiple genera are involved in these infections and different organisms can result in distinct clinical pictures. Differences in clinical and parasitologic response to various therapeutic agents have emerged from clinical, as well as in vitro and in vivo studies. Currently there are no precisely defined guidelines for the optimal treatment of microsporidial infections. This article reviews the available data on compounds with in vitro activity and/or in vivo efficacy for microsporidial infections. Copyright 2000 Harcourt Publishers Ltd.
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Affiliation(s)
- Sylvia F. Costa
- Department of Medicine, Division of Infectious Diseases, Albert Einstein College of Medicine, Bronx, New York, USA
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36
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Molina JM, Goguel J, Sarfati C, Michiels JF, Desportes-Livage I, Balkan S, Chastang C, Cotte L, Maslo C, Struxiano A, Derouin F, Decazes JM. Trial of oral fumagillin for the treatment of intestinal microsporidiosis in patients with HIV infection. ANRS 054 Study Group. Agence Nationale de Recherche sur le SIDA. AIDS 2000; 14:1341-8. [PMID: 10930148 DOI: 10.1097/00002030-200007070-00006] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Intestinal microsporidiosis caused by Enterocytozoon bieneusi is a cause of chronic diarrhoea in patients with HIV infection for which there is no current therapy. This study was designed to assess the safety and efficacy of oral fumagillin in this infection. DESIGN A dose-escalation trial. METHODS Twenty-nine HIV-infected patients with E. bieneusi infection were consecutively enrolled in the trial. Oral doses of fumagillin were given to four groups of patients for 14 days: 10 mg/day (group 1), 20 mg/day (group 2), 40 mg/day (group 3), and 60 mg/day (group 4). Patients were seen at weeks 1, 2, 4 and 6 to assess safety and efficacy. Efficacy was assessed primarily by the clearance of microsporidia from stools and follow-up duodenal biopsies. RESULTS Thirteen patients complained of abdominal cramps, vomiting or diarrhoea during the study, and three patients had fumagillin withdrawn because of adverse events. Thrombocytopenia, neutropenia and hyperlipasaemia were the most frequent biological adverse events. Twenty-one out of 29 patients transiently cleared microsporidia from their stools during the study. By week 6, however, all patients in groups 1, 2 and 3 had parasitic relapse. Interestingly, eight out of 11 (72%) patients treated with 60 mg/day (group 4) apparently cleared microsporidia from their gastrointestinal tract and gained weight. No parasitic relapse was documented in these eight patients during a mean follow-up of 11.5 months. CONCLUSION Treatment with fumagillin at 60 mg/day for 14 days has promise as an effective oral treatment for E. bieneusi infections.
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Affiliation(s)
- J M Molina
- Department of Infectious Diseases, Hôpital Saint-Louis, Paris, France.
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Fournier S, Liguory O, Sarfati C, David-Ouaknine F, Derouin F, Decazes JM, Molina JM. Disseminated infection due to Encephalitozoon cuniculi in a patient with AIDS: case report and review. HIV Med 2000; 1:155-61. [PMID: 11737344 DOI: 10.1046/j.1468-1293.2000.00022.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE AND METHODS Infections due to microsporidia are increasingly recognized as opportunistic infections in patients with AIDS. We describe here a case of disseminated infection due to Encephalitozoon cuniculi and review the literature on this microsporidial infection. RESULTS All 12 patients reported in the literature had AIDS and nine presented with disseminated infection involving the kidneys, sinuses, lungs, brain and conjunctiva. Asymptomatic infection was seen in three patients. Microsporidia were detected by light microscopy examination of urine samples in all the cases. Species identification was performed by various genotypic methods or transmission electron microscopy. Eight of 12 patients who received albendazole therapy experienced clinical improvement with documented clearance of spores in five of these eight patients. Two patients relapsed. CONCLUSIONS E. cuniculi infection should be considered in severely immunocompromised HIV-infected patients with multi-organ involvement and fever, especially when renal failure is present. Microsporidial spores are usually seen in urine samples and in the involved organ. Albendazole therapy seems to be effective.
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Affiliation(s)
- S Fournier
- Department of Infectious Diseases, Saint-Louis Hospital, Paris, France
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38
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Brugère JF, Cornillot E, Méténier G, Vivarès CP. Occurence of subtelomeric rearrangements in the genome of the microsporidian parasite Encephalitozoon cuniculi, as revealed by a new fingerprinting procedure based on two-dimensional pulsed field gel electrophoresis. Electrophoresis 2000; 21:2576-81. [PMID: 10939475 DOI: 10.1002/1522-2683(20000701)21:12<2576::aid-elps2576>3.0.co;2-d] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In Microsporidia, mitochondria-lacking eukaryotic intracellular parasites, genomic comparisons were so far based on molecular karyotyping. The mammal-infecting species Encephalitozoon cuniculi is characterized by a very low haploid genome size (approximately 2.8 Mbp) and rather high karyotype variability. Recently, we developed a two-dimensional pulsed field gel electrophoresis (2-D PFGE) fingerprinting technique useful for constructing a restriction map fo the genome of a mouse E. cuniculi isolate (karyotype variant A). The so-called karyotype and restriction display 2-D PFGE (KARD-PFGE) protocol involved 1-D chromosome separation, digestion with a rare cutter, Klenow radiolabeling of genomic DNA and 2-D separation of restriction fragments followed by autoradiography. In order to assess its suitability for detecting polymorphic loci in E. cuniculi, we applied KARD-PFGE with either BssHII or Mlul digestion to genome analysis of two rabbit isolates representative of two different karyotype variants (A and C). The 2-D spot pattern of the rabbit isolate variant A is identical to the reference mouse isolate but differs greatly from the rabbit isolate variant C. Chromosomal restriction fragment length polymorphisms (RFLPs) provide strong evidence for homologous chromosomes and frequent DNA rearrangements within subtelomeric regions just upstream of the dispersed rDNA units closely associated with each chromosomal end.
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Affiliation(s)
- J F Brugère
- Laboratoire de Parasitologie Moléculaire et Cellulaire, Université Blaise Pascal, Aubière, France
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Brugère JF, Cornillot E, Méténier G, Bensimon A, Vivarès CP. Encephalitozoon cuniculi (Microspora) genome: physical map and evidence for telomere-associated rDNA units on all chromosomes. Nucleic Acids Res 2000; 28:2026-33. [PMID: 10773069 PMCID: PMC105373 DOI: 10.1093/nar/28.10.2026] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A restriction map of the 2.8-Mb genome of the unicellular eukaryote Encephalitozoon cuniculi (phylum Microspora), a mammal-infecting intracellular parasite, has been constructed using two restriction enzymes with 6 bp recognition sites (Bss HII and Mlu I). The fragments resulting from either single digestions of the whole molecular karyotype or double digestions of 11 individual chromosomes have been separated by two-dimensional pulsed field gel electrophoresis (2D-PFGE) procedures. The average distance between successive restriction sites is approximately 19 kb. The terminal regions of the chromosomes show a common pattern covering approximately 15 kb and including one 16S-23S rDNA unit. Results of hybridisation and molecular combing experiments indicate a palindromic-like orientation of the two subtelomeric rDNA copies on each chromosome. We have also located 67 DNA markers (clones from a partial E. cuniculi genomic library) by hybridisation to restriction fragments. Partial or complete sequencing has revealed homologies with known protein-coding genes for 32 of these clones. Evidence for two homologous chromosomes III, with a size difference (3 kb) related to a subtelomeric deletion/insertion event, argues for diploidy of E.cuniculi. The physical map should be useful for both the whole genome sequencing project and studies on genome plasticity of this widespread parasite.
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Affiliation(s)
- J F Brugère
- Equipe de Parasitologie Moléculaire et Cellulaire, UPRES A CNRS 6023, Université Blaise Pascal, 63177 Aubière cedex, France
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40
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Wolk DM, Johnson CH, Rice EW, Marshall MM, Grahn KF, Plummer CB, Sterling CR. A spore counting method and cell culture model for chlorine disinfection studies of Encephalitozoon syn. Septata intestinalis. Appl Environ Microbiol 2000; 66:1266-73. [PMID: 10742198 PMCID: PMC91979 DOI: 10.1128/aem.66.4.1266-1273.2000] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/1999] [Accepted: 12/15/1999] [Indexed: 11/20/2022] Open
Abstract
The microsporidia have recently been recognized as a group of pathogens that have potential for waterborne transmission; however, little is known about the effects of routine disinfection on microsporidian spore viability. In this study, in vitro growth of Encephalitozoon syn. Septata intestinalis, a microsporidium found in the human gut, was used as a model to assess the effect of chlorine on the infectivity and viability of microsporidian spores. Spore inoculum concentrations were determined by using spectrophotometric measurements (percent transmittance at 625 nm) and by traditional hemacytometer counting. To determine quantitative dose-response data for spore infectivity, we optimized a rabbit kidney cell culture system in 24-well plates, which facilitated calculation of a 50% tissue culture infective dose (TCID(50)) and a minimal infective dose (MID) for E. intestinalis. The TCID(50) is a quantitative measure of infectivity and growth and is the number of organisms that must be present to infect 50% of the cell culture wells tested. The MID is as a measure of a system's permissiveness to infection and a measure of spore infectivity. A standardized MID and a standardized TCID(50) have not been reported previously for any microsporidian species. Both types of doses are reported in this paper, and the values were used to evaluate the effects of chlorine disinfection on the in vitro growth of microsporidia. Spores were treated with chlorine at concentrations of 0, 1, 2, 5, and 10 mg/liter. The exposure times ranged from 0 to 80 min at 25 degrees C and pH 7. MID data for E. intestinalis were compared before and after chlorine disinfection. A 3-log reduction (99.9% inhibition) in the E. intestinalis MID was observed at a chlorine concentration of 2 mg/liter after a minimum exposure time of 16 min. The log(10) reduction results based on percent transmittance-derived spore counts were equivalent to the results based on hemacytometer-derived spore counts. Our data suggest that chlorine treatment may be an effective water treatment for E. intestinalis and that spectrophotometric methods may be substituted for labor-intensive hemacytometer methods when spores are counted in laboratory-based chlorine disinfection studies.
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Affiliation(s)
- D M Wolk
- University of Arizona, Tucson, Arizona 85721, USA
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41
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Abstract
A variety of pharmacologic agents are currently available to treat house rabbits. In many cases, dosages are based on extrapolation from other species or empirical data. Dosing in rabbits is further complicated by individual variation. An understanding of rabbit physiology and the pharmacology of prescribed medications helps ensure that the agents are used as effectively and safely as possible. In this article, basic rabbit pharmacobiology is reviewed and techniques for drug administration are described. A formulary for house rabbits is provided.
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Affiliation(s)
- E S Ivey
- Avian/Exotic Service, Animal Medical Center, New York, New York, USA
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42
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Speare DJ, Athanassopoulou F, Daley J, Sanchez JG. A preliminary investigation of alternatives to fumagillin for the treatment of Loma salmonae infection in rainbow trout. J Comp Pathol 1999; 121:241-8. [PMID: 10486160 DOI: 10.1053/jcpa.1999.0325] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The effects of the following six treatments against Loma salmonae, a microsporidian gill pathogen, were examined in rainbow trout: fumagillin (high dose), pyrimethamine + sulphaquinoxaline, albendazole, amprolium, fumagillin (low dose), and metronidazole. The fish were infected by mouth and the treatments were administered at intervals for a period of several weeks. The results were assessed on the basis of (1) delay in the formation of xenomas, and (2) the number of xenomas per gill arch. The first five treatments, in descending order of efficacy, delayed the formation of xenomas (P<0.01), but metronidazole had no such effect. Fumagillin (high or low dose) and albendazole both reduced the number of xenomas present 10 weeks after infection (P<0.01), but the other three treatments did not do so. From these results, both fumagillin and albendazole appeared to be of potential value in controlling L. salmonae infection in trout.
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Affiliation(s)
- D J Speare
- Department of Pathology and Microbiology, Atlantic Veterinary College, Charlottetown, Prince Edward Island, C1A 4P3, Canada
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43
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Ridoux O, Drancourt M. Lack of in vitro antimicrosporidian activity of thalidomide. Antimicrob Agents Chemother 1999; 43:2305-6. [PMID: 10471585 PMCID: PMC89467 DOI: 10.1128/aac.43.9.2305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thalidomide was evaluated for its in vitro activity against Encephalitozoon species by using the MRC-5 cell system. A cytotoxic effect was observed for concentrations of 10(1) microg/ml (P < 10(5)) and 5 microg/ml (P < 10(5)). Thalidomide did not significantly inhibit the growth of any of the microsporidia under study. These data suggest that thalidomide is not an etiologic treatment in microsporidial enteritis.
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Affiliation(s)
- O Ridoux
- Unité des Rickettsies, CNRS UPRES-A 6020, Faculté de Médecine, Université de la Méditerranée, Marseille, France
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44
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Franzen C, Müller A. Molecular techniques for detection, species differentiation, and phylogenetic analysis of microsporidia. Clin Microbiol Rev 1999; 12:243-85. [PMID: 10194459 PMCID: PMC88917 DOI: 10.1128/cmr.12.2.243] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. These parasites are now recognized as one of the most common pathogens in human immunodeficiency virus-infected patients. For most patients with infectious diseases, microbiological isolation and identification techniques offer the most rapid and specific determination of the etiologic agent. This is not a suitable procedure for microsporidia, which are obligate intracellular parasites requiring cell culture systems for growth. Therefore, the diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Although the diagnosis of microsporidiosis and identification of microsporidia by light microscopy have greatly improved during the last few years, species differentiation by these techniques is usually impossible and transmission electron microscopy may be necessary. Immunfluorescent-staining techniques have been developed for species differentiation of microsporidia, but the antibodies used in these procedures are available only at research laboratories at present. During the last 10 years, the detection of infectious disease agents has begun to include the use of nucleic acid-based technologies. Diagnosis of infection caused by parasitic organisms is the last field of clinical microbiology to incorporate these techniques and molecular techniques (e.g., PCR and hybridization assays) have recently been developed for the detection, species differentiation, and phylogenetic analysis of microsporidia. In this paper we review human microsporidial infections and describe and discuss these newly developed molecular techniques.
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Affiliation(s)
- C Franzen
- Department of Internal Medicine I, University of Cologne, 50924 Cologne,
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45
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Ridoux O, Drancourt M. In vitro susceptibilities of the microsporidia Encephalitozoon cuniculi, Encephalitozoon hellem, and Encephalitozoon intestinalis to albendazole and its sulfoxide and sulfone metabolites. Antimicrob Agents Chemother 1998; 42:3301-3. [PMID: 9835533 PMCID: PMC106041 DOI: 10.1128/aac.42.12.3301] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In vitro comparisons demonstrated that the efficacy of albendazole, albendazole-sulfoxide, and albendazole-sulfone against pathogenic Encephalitozoon species was proportional to the degree of oxidation at a concentration of >10(-3) microgram/ml. Furthermore, at a concentration of <10(-2) microgram/ml, benzimidazoles were more effective against Encephalitozoon cuniculi and Encephalitozoon hellem than against Encephalitozoon intestinalis.
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Affiliation(s)
- O Ridoux
- Unité des Rickettsies CNRS UPRES-A 6020, Faculté de Médecine, Université de la Méditerranée, 13385 Marseille cedex 05, France
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46
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Speare DJ, Ritter G, Schmidt H. Quinine hydrochloride treatment delays xenoma formation and dissolution in rainbow trout challenged with Loma salmonae. J Comp Pathol 1998; 119:459-65. [PMID: 9839206 DOI: 10.1016/s0021-9975(98)80039-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
An experiment was designed to study the effect of dietary quinine hydrochloride (61 mg/kg of fish/day), on the rate of xenoma formation in the gills of Loma salmonae-infected juvenile rainbow trout maintained at a water temperature of 15 degrees C. Almost all (90.9%) control fish had developed xenomas by week 6 post-exposure (PE), but significantly fewer (18.2%) of the medicated fish were similarly affected (P < 0.0001). By week 8 PE, 100% of control fish had xenomas, but only 57.5% of quinine-treated had xenomas (P < 0.0001). However, by week 9 there was no difference between treated and control fish. Xenoma dissolution and branchitis, two crucial events in the pathogenesis of L. salmonae infection in farm-reared Pacific salmon, were present at week 10 in control fish. In contrast, comparable lesions did not develop in treated fish until week 14. These findings are of potential significance for the control of L. salmonae infection in farmed salmon.
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Affiliation(s)
- D J Speare
- Department of Pathology and Microbiology, University of Prince Edward Island, Charlottetown, Canada
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47
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Delbac F, Peyret P, Méténier G, David D, Danchin A, Vivarès CP. On proteins of the microsporidian invasive apparatus: complete sequence of a polar tube protein of Encephalitozoon cuniculi. Mol Microbiol 1998; 29:825-34. [PMID: 9723921 DOI: 10.1046/j.1365-2958.1998.00975.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The microsporidian Encephalitozoon cuniculi is an obligate intracellular parasite that can cause opportunistic infections in AIDS patients. Spore invasion of host cells involves extrusion of a polar tube. After immunocytochemical identification of several polar tube proteins (PTPs) in E. cuniculi, a major PTP was isolated from two-dimensional gels and two peptide fragments were sequenced. The complete nucleotide sequence of the corresponding gene was obtained using a combination of PCR amplification and cloning techniques. The gene exists as a single copy per haploid genome and encodes an acidic proline-rich protein, with a deduced molecular mass of 37 kDa, that contains four tandemly arranged 26-amino-acid repeats. An N-terminal region of 22 residues represents a cleaved signal peptide, probably involved in the targeting of the PTP. No similarity with known proteins has been found. The protein was expressed in Escherichia coli, purified and injected into mice. The antisera reacted specifically with the polar tube in indirect immunofluorescence assays and electron microscope immunocytochemistry. Further identification of conserved and variable PTP structural motifs should be useful for diagnostic purposes and new therapeutic strategies.
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Affiliation(s)
- F Delbac
- Protistologie Moléculaire et Cellulaire des Parasites Opportunistes, LBCP, UPESA CNRS 6023, Université Blaise Pascal, Aubière, France
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48
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Delbac F, Duffieux F, David D, Metenier G, Vivares CP. Immunocytochemical identification of spore proteins in two microsporidia, with emphasis on extrusion apparatus. J Eukaryot Microbiol 1998; 45:224-31. [PMID: 9561775 DOI: 10.1111/j.1550-7408.1998.tb04529.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Microsporidia can form small spores with a unique invasive apparatus featuring a long polar tube whose extrusion allows entry of infectious sporoplasm into a host cell. The reactivity of mouse polyclonal antibodies raised against sporal proteins from two microsporidian species belonging to different genera (Glugea atherinae and Encephalitozoon cuniculi) was studied by western blotting and indirect immunofluorescence. Whole protein antisera provided a few cross-reactions relatable to some proteins of the spore envelope or polar tube. Ultrastructural immunocytochemistry with murine antibodies against protein bands separated by sodium dodecylsulphate polyacrylamide gel electrophoresis allowed the assignment of several proteins to the polar tube (34, 75 and 170 kDa in Glugea, 35, 55 and 150 kDa in Encephalitozoon). Antigenic similarities were detected for the Glugea 34 kDa and Encephalitozoon 35 kDa polar tube proteins. Species-specific proteins were shown to be located in either the lamellar polaroplast of Glugea or the spore envelope of Encephalitozoon.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Protozoan/immunology
- Antigens, Protozoan/analysis
- Antigens, Protozoan/chemistry
- Antigens, Protozoan/immunology
- Blotting, Western
- Electrophoresis, Polyacrylamide Gel
- Encephalitozoon cuniculi/chemistry
- Encephalitozoon cuniculi/immunology
- Encephalitozoon cuniculi/ultrastructure
- Fishes
- Fluorescent Antibody Technique, Indirect
- Immunohistochemistry
- Mice
- Mice, Inbred BALB C
- Microscopy, Electron
- Microsporida/chemistry
- Microsporida/immunology
- Microsporida/ultrastructure
- Protozoan Proteins/analysis
- Protozoan Proteins/chemistry
- Protozoan Proteins/immunology
- Species Specificity
- Spores/chemistry
- Spores/immunology
- Spores/ultrastructure
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Affiliation(s)
- F Delbac
- LBCP, UPESA CNRS 6023, Université Blaise Pascal, Aubière, France
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49
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Katiyar SK, Edlind TD. In vitro susceptibilities of the AIDS-associated microsporidian Encephalitozoon intestinalis to albendazole, its sulfoxide metabolite, and 12 additional benzimidazole derivatives. Antimicrob Agents Chemother 1997; 41:2729-32. [PMID: 9420047 PMCID: PMC164197 DOI: 10.1128/aac.41.12.2729] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Recent reports have described the successful treatment of Encephalitozoon intestinalis infection in AIDS patients with albendazole. However, this compound is rapidly metabolized in vivo to albendazole sulfoxide, and furthermore it is only 1 of about 15 commercially developed benzimidazole derivatives. To compare the activities of albendazole, albendazole sulfoxide, and other benzimidazoles, an in vitro system involving infection of green monkey kidney cell (E6) monolayers with E. intestinalis spores was developed. After 14 days, the effects of benzimidazoles on spore production were determined. Ten of fourteen derivatives tested, including albendazole, were inhibitory at concentrations of 1 to 10 ng/ml. Derivatives modified at the 1 or 2 position were less active. Albendazole sulfoxide was 1.7-fold more inhibitory than albendazole but significantly less toxic to E6 cells, a finding that explains the clinical efficacy of this compound. Potential alternatives to albendazole are discussed. No albendazole-resistant E. intestinalis mutants were obtained following in vitro selection.
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Affiliation(s)
- S K Katiyar
- MCP-Hahnemann School of Medicine, Allegheny University of the Health Sciences, Philadelphia, Pennsylvania 19129, USA.
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Molina JM, Goguel J, Sarfati C, Chastang C, Desportes-Livage I, Michiels JF, Maslo C, Katlama C, Cotte L, Leport C, Raffi F, Derouin F, Modaï J. Potential efficacy of fumagillin in intestinal microsporidiosis due to Enterocytozoon bieneusi in patients with HIV infection: results of a drug screening study. The French Microsporidiosis Study Group. AIDS 1997; 11:1603-10. [PMID: 9365765 DOI: 10.1097/00002030-199713000-00009] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Intestinal microsporidiosis due to Enterocytozoon bieneusi is a frequent cause of chronic diarrhoea in patients with HIV infection for which there is no available therapy. This study was designed to search for a drug with activity against this organism. DESIGN Prospective open-labelled Phase II multicentre study. SETTING University hospitals. PATIENTS Sixty HIV-infected men with intestinal E. bieneusi infection. INTERVENTIONS Ten drug regimens were consecutively tested orally for 3 weeks: albendazole plus metronidazole, sulphadiazine plus pyrimethamine, atovaquone, doxycycline plus nifuroxazide, itraconazole, flubendazole, chloroquine, paromomycin, sparfloxacin and fumagillin. Nine evaluable patients per regimen were required, but each patient could be enrolled up to three times in the study. OUTCOME MEASURE Efficacy was assessed primarily by the clearance of E. bieneusi from stools and intestinal biopsies. The safety of each regimen was also assessed. RESULTS Only purified fumagillin was able to clear E. bieneusi from stools as well as intestinal biopsies, whereas all other regimens failed to show antiparasitic efficacy. However, only four patients received fumagillin because of drug-induced thrombocytopenia. The four patients who received fumagillin remained free of E. bieneusi infection after a mean follow-up of 10 months. CONCLUSION Eradication of E. bieneusi from the intestinal tract of patients with HIV infection and persistent immunosuppression is an achievable goal. Our study allowed the identification of oral fumagillin as a potential treatment for intestinal microsporidiosis due to E. bieneusi.
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