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Torres-Machorro AL, Hernández R, Cevallos AM, López-Villaseñor I. Ribosomal RNA genes in eukaryotic microorganisms: witnesses of phylogeny? FEMS Microbiol Rev 2010; 34:59-86. [DOI: 10.1111/j.1574-6976.2009.00196.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Molecular diagnostic tests for microsporidia. Interdiscip Perspect Infect Dis 2009; 2009:926521. [PMID: 19657457 PMCID: PMC2719812 DOI: 10.1155/2009/926521] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 05/12/2009] [Indexed: 11/29/2022] Open
Abstract
The Microsporidia are a ubiquitous group of eukaryotic obligate intracellular parasites which were recognized over 100 years ago with the description of Nosema bombycis, a parasite of silkworms. It is now appreciated that these organisms are related to the Fungi. Microsporidia infect all major animal groups most often as gastrointestinal pathogens; however they have been reported from every tissue and organ, and their spores are common in environmental sources such as ditch water. Several different genera of these organisms infect humans, but the majority of infections are due to either
Enterocytozoon bieneusi or Encephalitozoon species. These pathogens can be difficult to diagnose, but significant progress has been made in the last decade in the development of molecular diagnostic reagents for these organisms. This report reviews the molecular diagnostic tests that have been described for the identification of the microsporidia that infect humans.
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Identification of Encephalitozoon cuniculi genotype III and two novel genotypes of Enterocytozoon bieneusi in swine. Parasitol Int 2009; 58:285-92. [PMID: 19318131 DOI: 10.1016/j.parint.2009.03.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 02/19/2009] [Accepted: 03/13/2009] [Indexed: 11/20/2022]
Abstract
Samples of intestinal content from thirty fattened pigs of six farms slaughtered at an abattoir in North-Western Germany, and faecal samples of four pigs kept as laboratory animals at the Federal Institute for Risk Assessment (BfR, Berlin, Germany) were investigated for the occurrence of microsporidia by light microscopy, PCR and sequencing. A modified Webers trichrome staining and the immunohistochemistry (the Avidin-Biotin-Peroxidase-Complex technique with a polyclonal anti-Encephalitozoon cuniculi-serum and monoclonal antibodies against Encephalitozoon intestinalis and Enterocytozoon bieneusi) was used as a screening method for the light microscopical detection of these pathogenic eukaryotes. By this light microscopically methods microsporidia suspected organisms were found in all samples (100%). By the use of PCR, microsporidia were identified in fourteen samples (41.2%). The prevalence of microsporidia infections among the farms diversifies from 0 to 80% as considered by PCR. E. bieneusi was the most prevalent species and was identified in twelve fattened pigs (40%) from five of the six tested farms (83.3%) and in two of the four laboratory animals (50%). Three of the E. bieneusi species belonged to the genotype O, one to the genotype E, and one to the genotype F. Two isolates were identified as novel genotypes and two samples showed a mixed infection of different genotypes. In three faecal samples of the pigs from two farms E. cuniculi genotype III was identified. One sample contained both microsporidia species. To our knowledge, this is the first time that the genotype III of E. cuniculi was identified in swine.
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Akiyoshi DE, Morrison HG, Lei S, Feng X, Zhang Q, Corradi N, Mayanja H, Tumwine JK, Keeling PJ, Weiss LM, Tzipori S. Genomic survey of the non-cultivatable opportunistic human pathogen, Enterocytozoon bieneusi. PLoS Pathog 2009; 5:e1000261. [PMID: 19132089 PMCID: PMC2607024 DOI: 10.1371/journal.ppat.1000261] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Accepted: 12/11/2008] [Indexed: 11/28/2022] Open
Abstract
Enterocytozoon bieneusi is the most common microsporidian associated with human disease, particularly in the immunocompromised population. In the setting of HIV infection, it is associated with diarrhea and wasting syndrome. Like all microsporidia, E. bieneusi is an obligate, intracellular parasite, but unlike others, it is in direct contact with the host cell cytoplasm. Studies of E. bieneusi have been greatly limited due to the absence of genomic data and lack of a robust cultivation system. Here, we present the first large-scale genomic dataset for E. bieneusi. Approximately 3.86 Mb of unique sequence was generated by paired end Sanger sequencing, representing about 64% of the estimated 6 Mb genome. A total of 3,804 genes were identified in E. bieneusi, of which 1,702 encode proteins with assigned functions. Of these, 653 are homologs of Encephalitozoon cuniculi proteins. Only one E. bieneusi protein with assigned function had no E. cuniculi homolog. The shared proteins were, in general, evenly distributed among the functional categories, with the exception of a dearth of genes encoding proteins associated with pathways for fatty acid and core carbon metabolism. Short intergenic regions, high gene density, and shortened protein-coding sequences were observed in the E. bieneusi genome, all traits consistent with genomic compaction. Our findings suggest that E. bieneusi is a likely model for extreme genome reduction and host dependence. Enterocytozoon bieneusi is a clinically significant pathogen associated with human microsporidiosis, particularly in immunocompromised individuals. E. bieneusi is widespread in mammals, and there is no effective commercial treatment for infection. The pathogen cannot be readily cultivated, and animal models are limited. We therefore undertook a sequence survey and generated the first large-scale genomic dataset for E. bieneusi, which we used to study the organization and structure of its genome and to perform a comparative analysis with Encephalitozoon cuniculi, another microsporidian whose genome has been completely sequenced. The E. bieneusi genome showed many traits associated with genome compaction including high gene density, short intergenic regions, shortened proteins, and few introns. With one exception, all E. bieneusi proteins with assigned functions had E. cuniculi homologs. We found a paucity of genes encoding proteins associated with fatty acid and carbon metabolism. The possibility that these core functions are reduced in an intracellular parasite is intriguing, but because the genome sequence of E. bieneusi is incomplete, we cannot exclude the possibility that additional proteins associated with the various metabolic pathways would be discovered in a completed genome.
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Affiliation(s)
- Donna E Akiyoshi
- Department of Biomedical Sciences, Division of Infectious Diseases, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachusetts, United States of America.
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Fischer J, Tran D, Juneau R, Hale-Donze H. Kinetics of Encephalitozoon Spp. Infection of Human Macrophages. J Parasitol 2008; 94:169-75. [DOI: 10.1645/ge-1303.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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57
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Affiliation(s)
- Frédéric Delbac
- Equipe Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, 24 Avenue des Landais 63177 Aubière, France.
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58
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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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Abstract
Waterborne trematode and protozoan infections inflict considerable morbidity on healthy, i.e., immunocompetent people, and may cause life-threatening diseases among immunocompromised and immunosuppressed populations. These infections are common, easily transmissible, and maintain a worldwide distribution, although waterborne trematode infections remain predominantly confined to the developing countries. Waterborne transmission of trematodes is enhanced by cultural practices of eating raw or inadequately cooked food, socio-economical factors, and wide zoonotic and sylvatic reservoirs of these helminths. Waterborne protozoan infections remain common in both developed and developing countries (although better statistics exist for developed countries), and their transmission is facilitated via contacts with recreational and surface waters, or via consumption of contaminated drinking water. The transmissive stages of human protozoan parasites are small, shed in large numbers in feces of infected people or animals, resistant to environmental stressors while in the environment, and few are (e.g., Cryptosporidium oocysts) able to resist standard disinfection applied to drinking water.
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Affiliation(s)
- Thaddeus K Graczyk
- Division of Environmental Health Engineering, Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
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60
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Joh SJ, Kwon YK, Kim MC, Kim MJ, Kwon HM, Park JW, Kwon JH, Kim JH. Heterosporis anguillarum infections in farm cultured eels (Anguilla japonica) in Korea. J Vet Sci 2007; 8:147-9. [PMID: 17519567 PMCID: PMC2872712 DOI: 10.4142/jvs.2007.8.2.147] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Ten eels (Anguilla japonica) from a fish farm in Korea were examined and diagnosed with a Heterosporis infection. The gross lesions on the trunk were uneven and the concave parts were pasty. Histopathologically, lyses of the trunk muscles, degenerative muscle fibers and the scattered spores were observed. The sporophorocyst (SPC) contained several spores with a variety of shapes. Some SPC were disrupted and the spores in the SPC were scattered in the muscle tissues. Macrophages existed near the scattered spores. Electron microscopy revealed special structures such as sporophorocyst containing various developmental parasitic stages such as meronts, sporonts, sporophorous vesicles and spores.
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Affiliation(s)
- Seong Joon Joh
- National Veterinary Research and Quarantine Service, Ministry of Agriculture and Forestry, Anyang, Korea.
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61
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Jedrzejewski S, Graczyk TK, Slodkowicz-Kowalska A, Tamang L, Majewska AC. Quantitative assessment of contamination of fresh food produce of various retail types by human-virulent microsporidian spores. Appl Environ Microbiol 2007; 73:4071-3. [PMID: 17449682 PMCID: PMC1932721 DOI: 10.1128/aem.00477-07] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study demonstrated that fresh food produce, such as berries, sprouts, and green-leafed vegetables, sold at the retail level can contain potentially viable microsporidian spores of human-virulent species, such as Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Encephalitozoon cuniculi, at quantities representing a threat of food-borne infection.
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Affiliation(s)
- Szymon Jedrzejewski
- Department of Biology and Medical Parasitology, Poznan University of Medical Sciences, Poland
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62
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Graczyk TK, Kacprzak M, Neczaj E, Tamang L, Graczyk H, Lucy FE, Girouard AS. Human-virulent microsporidian spores in solid waste landfill leachate and sewage sludge, and effects of sanitization treatments on their inactivation. Parasitol Res 2007; 101:569-75. [PMID: 17364164 DOI: 10.1007/s00436-007-0515-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Accepted: 03/04/2007] [Indexed: 11/25/2022]
Abstract
Solid waste landfill leachate and sewage sludge samples were quantitatively tested for viable Enterocytozoon bieneusi, Encephalitozoon intestinalis, Encephalitozoon hellem, and Encephalitozoon cuniculi spores by the multiplexed fluorescence in situ hybridization (FISH) assay. The landfill leachate samples tested positive for E. bieneusi and the sludge samples for E. bieneusi and E. intestinalis. The effects of four sanitization treatments on the inactivation of these pathogens were assessed. Depending on the variations utilized in the ultrasound disintegration, sonication reduced the load of human-virulent microsporidian spores to nondetectable levels in 19 out of 27 samples (70.4%). Quicklime stabilization was 100% effective, whereas microwave energy disintegration was 100% ineffective against the spores of E. bieneusi and E. intestinalis. Top-soil stabilization treatment gradually reduced the load of both pathogens, consistent with the serial dilution of sewage sludge with the soil substrate. This study demonstrated that sewage sludge and landfill leachate contained high numbers of viable, human-virulent microsporidian spores, and that sonication and quicklime stabilization were the most effective treatments for the sanitization of sewage sludge and solid waste landfill leachates. Multiplexed FISH assay is a reliable quantitative molecular fluorescence microscopy method for the simultaneous identification of E. bieneusi, E. intestinalis, E. hellem, and E. cuniculi spores in environmental samples.
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Affiliation(s)
- Thaddeus K Graczyk
- Department of Environmental Health Sciences, Division of Environmental Health Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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63
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Graczyk TK, Johansson MA, Tamang L, Visvesvara GS, Moura LS, DaSilva AJ, Girouard AS, Matos O. Retrospective species identification of microsporidian spores in diarrheic fecal samples from human immunodeficiency virus/AIDS patients by multiplexed fluorescence in situ hybridization. J Clin Microbiol 2007; 45:1255-60. [PMID: 17287331 PMCID: PMC1865804 DOI: 10.1128/jcm.01975-06] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In order to assess the applicability of multiplexed fluorescence in situ hybridization (FISH) assay for the clinical setting, we conducted retrospective analysis of 110 formalin-stored diarrheic stool samples from human immunodeficiency virus (HIV)/AIDS patients with intestinal microsporidiosis collected between 1992 and 2003. The multiplexed FISH assay identified microsporidian spores in 94 of 110 (85.5%) samples: 49 (52.1%) were positive for Enterocytozoon bieneusi, 43 (45.8%) were positive for Encephalitozoon intestinalis, 2 (2.1%) were positive for Encephalitozoon hellem, and 9 samples (9.6%) contained both E. bieneusi and E. intestinalis spores. Quantitative spore counts per ml of stool yielded concentration values from 3.5 x 10(3) to 4.4 x 10(5) for E. bieneusi (mean, 8.8 x 10(4)/ml), 2.3 x 10(2) to 7.8 x 10(4) (mean, 1.5 x 10(4)/ml) for E. intestinalis, and 1.8 x 10(2) to 3.6 x 10(2) for E. hellem (mean, 2.7 x 10(2)/ml). Identification of microsporidian spores by multiplex FISH assay was more sensitive than both Chromotrope-2R and CalcoFluor White M2R stains; 85.5% versus 72.7 and 70.9%, respectively. The study demonstrated that microsporidian coinfection in HIV/AIDS patients with intestinal microsporidiosis is not uncommon and that formalin-stored fecal samples older than 10 years may not be suitable for retrospective analysis by techniques targeting rRNA. Multiplexed FISH assay is a reliable, quantitative fluorescence microscopy method for the simultaneous identification of E. bieneusi, E. intestinalis, and E. hellem, as well as Encephalitozoon cuniculi, spores in fecal samples and is a useful tool for assessing spore shedding intensity in intestinal microsporidiosis. The method can be used for epidemiological investigations and applied in clinical settings.
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Affiliation(s)
- Thaddeus K Graczyk
- Department of Environmental Health Sciences, Division of Environmental Health Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD 21205, USA.
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64
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Wang W, Chen J. Ultrastructural study on a novel microsporidian, Endoreticulatus eriocheir sp. nov. (Microsporidia, Encephalitozoonidae), parasite of Chinese mitten crab, Eriocheir sinensis (Crustacea, Decapoda). J Invertebr Pathol 2007; 94:77-83. [PMID: 17097104 DOI: 10.1016/j.jip.2006.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2005] [Revised: 09/14/2006] [Accepted: 09/25/2006] [Indexed: 10/23/2022]
Abstract
A microsporidian pathogen, infecting the epithelial cells of the hepatopancreas of Chinese mitten crab, Eriocheir sinensis, was studied by electron microscopy. The detailed ultrastructure of life cycle of the pathogen including proliferative and sporogonic developmental stages are provided. All stages of the parasite are haplokaryotic and develop in a vacuole bounded by a single membrane in contact with host cell cytoplasm. Sporogenesis is synchronous with the same developmental stage in one vacuole. Sporogony shows a characteristic of multinucleate sporogonial plasmodia divided by rosette-like division, producing 4 or 8 sporoblasts. The mature spore is ellipsoidal, length (mean) 1.7 microm, width 1.0 microm, with a uninucleate in the center of the sporoplasm, 7 turns of the polar filament, a bell-like polaroplast of compact membranes and obliquely positioned posterior vacuole. The morphological characteristics of this novel microsporidian pathogen have led us to assign the parasite to a new species of Endoreticulatus, E. eriocheir sp. nov., that has not been reported previously from crab.
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Affiliation(s)
- Wen Wang
- Department of Biological Science and Technology, Nanjing University, Nanjing 210093, P.R. China.
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65
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Slodkowicz-Kowalska A, Graczyk TK, Tamang L, Jedrzejewski S, Nowosad A, Zduniak P, Solarczyk P, Girouard AS, Majewska AC. Microsporidian species known to infect humans are present in aquatic birds: implications for transmission via water? Appl Environ Microbiol 2006; 72:4540-4. [PMID: 16820441 PMCID: PMC1489349 DOI: 10.1128/aem.02503-05] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human microsporidiosis, a serious disease of immunocompetent and immunosuppressed people, can be due to zoonotic and environmental transmission of microsporidian spores. A survey utilizing conventional and molecular techniques for examining feces from 570 free-ranging, captive, and livestock birds demonstrated that 21 animals shed microsporidian spores of species known to infect humans, including Encephalitozoon hellem (20 birds; 3.5%) and Encephalitozoon intestinalis (1 bird; 0.2%). Of 11 avian species that shed E. hellem and E. intestinalis, 8 were aquatic birds (i.e., common waterfowl). The prevalence of microsporidian infections in waterfowl (8.6%) was significantly higher than the prevalence of microsporidian infections in other birds (1.1%) (P < 0.03); waterfowl fecal droppings contained significantly more spores (mean, 3.6 x 10(5) spores/g) than nonaquatic bird droppings contained (mean, 4.4 x 10(4) spores/g) (P < 0.003); and the presence of microsporidian spores of species known to infect humans in fecal samples was statistically associated with the aquatic status of the avian host (P < 0.001). We demonstrated that a single visit of a waterfowl flock can introduce into the surface water approximately 9.1 x 10(8) microsporidian spores of species known to infect humans. Our findings demonstrate that waterborne microsporidian spores of species that infect people can originate from common waterfowl, which usually occur in large numbers and have unlimited access to surface waters, including waters used for production of drinking water.
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Affiliation(s)
- Anna Slodkowicz-Kowalska
- Departmetn of Biology and Medical Parasitology, Poznan University of Medical Sciences, Poznan, Poland
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66
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Peuvel-Fanget I, Polonais V, Brosson D, Texier C, Kuhn L, Peyret P, Vivarès C, Delbac F. EnP1 and EnP2, two proteins associated with the Encephalitozoon cuniculi endospore, the chitin-rich inner layer of the microsporidian spore wall. Int J Parasitol 2006; 36:309-18. [PMID: 16368098 DOI: 10.1016/j.ijpara.2005.10.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Revised: 09/28/2005] [Accepted: 10/25/2005] [Indexed: 11/30/2022]
Abstract
Microsporidia are obligate intracellular parasites forming environmentally resistant spores that harbour a rigid cell wall. This wall comprises an outer layer or exospore and a chitin-rich inner layer or endospore. So far, only a chitin deacetylase-like protein has been shown to localize to the Encephalitozoon cuniculi endospore and either one or two proteins have been clearly assigned to the exospore in two Encephalitozoon species: SWP1 in E. cuniculi, SWP1 and SWP2 in Encephalitozoon intestinalis. Here, we report the identification of two new spore wall proteins in E. cuniculi, EnP1 and EnP2, the genes of which are both located on chromosome I (ECU01_0820 and ECU01_1270, respectively) and have no known homologue. Detected by immunoscreening of an E. cuniculi cDNA library, enp1 is characterized by small-sized 5' and 3' untranslated regions and is highly expressed throughout the whole intracellular cycle. The encoded basic 40 kDa antigen displays a high proportion of cysteine residues, arguing for a significant role of disulfide bridges in spore wall assembly. EnP2 is a 22 kDa serine-rich protein that is predicted to be O-glycosylated and glycosylated phosphatidyl inositol-anchored. Although having been identified by mass spectrometry of a dithiothreitol-soluble fraction, this protein contains only two cysteine residues. Mouse polyclonal antibodies were raised against EnP1 and EnP2 recombinant proteins produced in Escherichia coli Our immunolocalisation data indicate that EnP1 and EnP2 are targeted to the cell surface as early as the onset of sporogony and are finally associated with the chitin-rich layer of the wall in mature spores.
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Affiliation(s)
- Isabelle Peuvel-Fanget
- Equipe Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière Cedex, France
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67
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Jordan CN, Zajac AM, Snowden KS, Lindsay DS. Direct agglutination test for Encephalitozoon cuniculi. Vet Parasitol 2006; 135:235-40. [PMID: 16229953 DOI: 10.1016/j.vetpar.2005.09.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Revised: 09/06/2005] [Accepted: 09/07/2005] [Indexed: 11/30/2022]
Abstract
Encephalitozoon cuniculi is a small protozoan parasite in the phylum Microspora. It has been shown to naturally infect several host species, including humans. Infection with microsporidia is usually asymptomatic, except in young or immunocompromised hosts. Currently, serological diagnosis of infection is made using the indirect immunofluorescent antibody assay (IFA) or enzyme-linked immunosorbent assay (ELISA). Although these methods are sensitive and reliable, there are several drawbacks to the IFA and ELISA tests. Cross-reactivity between other Encephalitozoon species is common, and specialized equipment is required to conduct these tests. This paper reports the development of a direct agglutination test for detecting IgG antibodies to E. cuniculi. The utility of the agglutination test was examined in CD-1 and C3H/He mice infected with E. cuniculi or one of 2 other Encephalitozoon species. Test sera were incubated overnight with eosin-stained microsporidia spores in round-bottom microtiter plates. In positive samples, agglutination of spores with antibodies in test sera resulted in an opaque mat spread across the well. The results indicate that the agglutination test is 86% sensitive and 98% specific for E. cuniculi, with limited cross-reactivity to Encephalitozoon intestinalis. No cross-reactivity to Encephalitozoon hellem was observed. The test is fast and easy to conduct, and species-specific antibodies are not required.
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Affiliation(s)
- Carly N Jordan
- Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, 1410 Prices Fork Road, Blacksburg, VA 24061-0342, USA
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68
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Peek R, Delbac F, Speijer D, Polonais V, Greve S, Wentink-Bonnema E, Ringrose J, van Gool T. Carbohydrate moieties of microsporidian polar tube proteins are targeted by immunoglobulin G in immunocompetent individuals. Infect Immun 2006; 73:7906-13. [PMID: 16299281 PMCID: PMC1307029 DOI: 10.1128/iai.73.12.7906-7913.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia of the Encephalitozoon species are frequently found as opportunistic pathogens of immunocompromised patients, but very little is known about the prevalence and significance of Encephalitozoon infection in immunocompetent individuals. It was reported previously that 8% of Dutch blood donors and 5% of pregnant French women had an immunoglobulin G (IgG) immune response against specific organelles of Encephalitozoon intestinalis. These organelles, the so-called polar tube and anchoring disk, are used to penetrate membranes of host cells during infection. The unexpectedly high percentage of immunocompetent individuals with IgG against these organelles suggested that infection of humans with microsporidia might be more common than previously recognized. In the present study, we analyzed this anti-Encephalitozoon IgG response by using indirect immunofluorescence, Western blotting, two-dimensional gel electrophoresis, and chemical deglycosylation. Our results show that the antibody response is directed against the posttranslational carbohydrate modification of the major polar tube protein (polar tube protein 1) and carbohydrate moieties of proteins in the anchoring region of the polar tube of Encephalitozoon. In addition, the antibodies were found to decrease the infectivity of E. intestinalis in vitro. The significance and possible origin of these prevalent antibodies are discussed.
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Affiliation(s)
- Ron Peek
- Section Parasitology, Department of Medical Microbiology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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69
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Walker M, Kublin JG, Zunt JR. Parasitic central nervous system infections in immunocompromised hosts: malaria, microsporidiosis, leishmaniasis, and African trypanosomiasis. Clin Infect Dis 2006; 42:115-25. [PMID: 16323101 PMCID: PMC2683841 DOI: 10.1086/498510] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2005] [Accepted: 08/04/2005] [Indexed: 11/03/2022] Open
Abstract
Immunosuppression associated with HIV infection or following transplantation increases susceptibility to central nervous system (CNS) infections. Because of increasing international travel, parasites that were previously limited to tropical regions pose an increasing infectious threat to populations at risk for acquiring opportunistic infection, especially people with HIV infection or individuals who have received a solid organ or bone marrow transplant. Although long-term immunosuppression caused by medications such as prednisone likely also increases the risk for acquiring infection and for developing CNS manifestations, little published information is available to support this hypothesis. In an earlier article published in Clinical Infectious Diseases, we described the neurologic manifestations of some of the more common parasitic CNS infections. This review will discuss the presentation, diagnosis, and treatment of the following additional parasitic CNS infections: malaria, microsporidiosis, leishmaniasis, and African trypanosomiasis.
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Affiliation(s)
- Melanie Walker
- Department of Neurology, University of Washington School of Medicine, Seattle, Washington
| | | | - Joseph R. Zunt
- Department of Neurology, University of Washington School of Medicine, Seattle, Washington
- Department of Medicine, Infectious Diseases Division, University of Washington School of Medicine, Seattle, Washington
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Pariyakanok L, Jongwutiwes S. Keratitis caused by Trachipleistophora anthropopthera. J Infect 2005; 51:325-8. [PMID: 16291286 DOI: 10.1016/j.jinf.2004.08.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/18/2004] [Indexed: 11/19/2022]
Abstract
We report a case of intrastromal keratitis in a 42-year-old male with underlying human immunodeficiency virus-1 infection. Numerous microsporidial spores were found from corneal biopsy. Ultrastructural studies of corneal tissues revealed dimorphic sporophorous vesicles containing characteristic spores belonging to Trachipleistophora anthropopthera. Infection could be controlled by penetrating keratoplasty but not by topical fumagillin and systemic albendazole per se. This is the first report of human keratitis caused by this organism.
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Affiliation(s)
- Lalida Pariyakanok
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Rama 4, Bangkok 10330, Thailand
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71
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Fielding NJ, MacNeil C, Robinson N, Dick JTA, Elwood RW, Terry RS, Ruiz Z, Dunn AM. Ecological impacts of the microsporidian parasite Pleistophora mulleri on its freshwater amphipod host Gammarus duebeni celticus. Parasitology 2005; 131:331-6. [PMID: 16178354 DOI: 10.1017/s0031182005007754] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The microsporidian parasite, Pleistophora mulleri, infects the abdominal muscle of the freshwater amphipod Gammarus duebeni celticus. We recently showed that P. mulleri infection was associated with G. d. celticus hosts being more vulnerable to predation by the invasive amphipod Gammarus pulex. Parasitized G. d. celticus also had a reduced ability to prey upon other co-occurring amphipods. We suggested the parasite may have pervasive influences on host ecology and behaviour. Here, we examine the association between P. mulleri parasitism and parameters influencing individual host fitness, behaviour and interspecific interactions. We also investigate the relationship between parasite prevalence and host population structure in the field. In our G. d. celticus study population, P. mulleri prevalence was strongly seasonal, ranging from 8.5% in summer to 44.9% in winter. The relative abundance of hosts with the heaviest parasite burden increased during summer, which coincided with high host mortality, suggesting that parasitism may regulate host abundance to some degree. Females were more likely to be parasitized than males and parasitized males were paired with smaller females than unparasitized males. Parasitism was associated with reduction in the host's activity level and reduced both its predation on the isopod Asellus aquaticus and aggression towards precopula pairs of the invasive G. pulex. We discuss the pervasive influence of this parasite on the ecology of its host.
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Affiliation(s)
- N J Fielding
- School of Biology and Biochemistry, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, N. Ireland, UK
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Ghosh K, Cappiello CD, McBride SM, Occi JL, Cali A, Takvorian PM, McDonald TV, Weiss LM. Functional characterization of a putative aquaporin from Encephalitozoon cuniculi, a microsporidia pathogenic to humans. Int J Parasitol 2005; 36:57-62. [PMID: 16197948 PMCID: PMC3086640 DOI: 10.1016/j.ijpara.2005.08.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Revised: 08/22/2005] [Accepted: 08/25/2005] [Indexed: 12/01/2022]
Abstract
The microsporidia are a group of obligate intracellular parasitic protists that have been implicated as both human and veterinary pathogens. The infectious process of these organisms is believed to be dependent upon the rapid influx of water into spores, presumably via aquaporins (AQPs), transmembrane channels that facilitate osmosis. An AQP-like sequence of the microsporidium Encephalitozoon cuniculi (EcAQP), when cloned and expressed in oocytes of Xenopus laevis, rendered these oocytes highly permeable to water. No permeability to the solutes glycerol or urea was observed. Pre-treatment of EcAQP-expressing oocytes with HgCl(2) failed to inhibit their osmotic permeability, as predicted from EcAQP's lack of mercury-sensitive cysteine residues near the NPA motifs which line the AQP aqueous pore. EcAQP exhibits sequence identity to AQP A of Dictyostelium discoideum (26%) and human AQP 2 (24%). Further study of AQPs in microsporidia and their potential inhibitors may yield novel therapeutic agents for microsporidian infections.
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Affiliation(s)
- Kaya Ghosh
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
- Department of Biological Sciences, 101 Warren Street, Smith Hall, Rutgers University, Newark, NJ 07102, USA
| | - Clint D. Cappiello
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
- Department of Biology, The College of New Jersey, P.O. Box 7718, Ewing, NJ 08628, USA
| | - Sean M. McBride
- Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - James L. Occi
- Department of Biological Sciences, 101 Warren Street, Smith Hall, Rutgers University, Newark, NJ 07102, USA
| | - Ann Cali
- Department of Biological Sciences, 101 Warren Street, Smith Hall, Rutgers University, Newark, NJ 07102, USA
| | - Peter M. Takvorian
- Department of Biological Sciences, 101 Warren Street, Smith Hall, Rutgers University, Newark, NJ 07102, USA
| | - Thomas V. McDonald
- Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Louis M. Weiss
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Corresponding author. Address: Department of Pathology, Albert Einstein College of Medicine, Yeshiva University, Rm F 504 1300 Morris Park Avenue, Bronx, NY 10461, USA. Tel.: C1 718 430 2142; fax: C1 718 430 8543. (L.M. Weiss)
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73
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Xu Y, Weiss LM. The microsporidian polar tube: a highly specialised invasion organelle. Int J Parasitol 2005; 35:941-53. [PMID: 16005007 PMCID: PMC3109658 DOI: 10.1016/j.ijpara.2005.04.003] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Revised: 03/28/2005] [Accepted: 04/05/2005] [Indexed: 11/30/2022]
Abstract
All of the members of the Microsporidia possess a unique, highly specialised structure, the polar tube. This article reviews the available data on the organisation, structure and function of this invasion organelle. It was over 100 years ago that Thelohan accurately described the microsporidian polar tube and the triggering of its discharge. In the spore, the polar tube is connected at the anterior end, and then coils around the sporoplasm. Upon appropriate environmental stimulation the polar tube rapidly discharges out of the spore pierces a cell membrane and serves as a conduit for sporoplasm passage into the new host cell. The mechanism of germination of spores, however, remains to be definitively determined. In addition, further studies on the characterisation of the early events in the rupture of the anterior attachment complex, eversion of the polar tube as well as the mechanism of host cell attachment and penetration are needed in order to clarify the function and assembly of this structure. The application of immunological and molecular techniques has resulted in the identification of three polar tube proteins referred to as PTP1, PTP2 and PTP3. The interactions of these identified proteins in the formation and function of the polar tube remain to be determined. Data suggest that PTP1 is an O-mannosylated glycoprotein, a post-translational modification that may be important for its function. With the availability of the Encephalitozoon cuniculi genome it is now possible to apply proteomic techniques to the characterisation of the components of the microsporidian spore and invasion organelle.
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Affiliation(s)
- Yanji Xu
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Louis M. Weiss
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Medicine, Albert Einstein College of Medicine, Room 504 Forchheimer Building, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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74
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Thomarat F, Vivarès CP, Gouy M. Phylogenetic analysis of the complete genome sequence of Encephalitozoon cuniculi supports the fungal origin of microsporidia and reveals a high frequency of fast-evolving genes. J Mol Evol 2005; 59:780-91. [PMID: 15599510 DOI: 10.1007/s00239-004-2673-0] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2003] [Accepted: 06/29/2004] [Indexed: 10/26/2022]
Abstract
Microsporidia are unicellular eukaryotes living as obligate intracellular parasites. Lacking mitochondria, they were initially considered as having diverged before the endosymbiosis at the origin of mitochondria. That microsporidia were primitively amitochondriate was first questioned by the discovery of microsporidial sequences homologous to genes encoding mitochondrial proteins and then refuted by the identification of remnants of mitochondria in their cytoplasm. Various molecular phylogenies also cast doubt on the early divergence of microsporidia, these organisms forming a monophyletic group with or within the fungi. The 2001 proteins putatively encoded by the complete genome of Encephalitozoon cuniculi provided powerful data to test this hypothesis. Phylogenetic analysis of 99 proteins selected as adequate phylogenetic markers indicated that the E. cuniculi sequences having the lowest evolutionary rates preferentially clustered with fungal sequences or, more rarely, with both animal and fungal sequences. Because sequences with low evolutionary rates are less sensitive to the long-branch attraction artifact, we concluded that microsporidia are evolutionarily related to fungi. This analysis also allowed comparing the accuracy of several phylogenetic algorithms for a fast-evolving lineage with real rather than simulated sequences.
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Affiliation(s)
- Fabienne Thomarat
- Laboratoire de Biométrie et Biologie Evolutive, UMR CNRS 5558, Université Claude Bernard Lyon I, 43 boulevard du 11 Novembre 1918, 69622 Villeurbanne, France
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75
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Becker JA, Speare DJ, Dohoo IR. Influence of feeding ratio and size on susceptibility to microsporidial gill disease caused by Loma salmonae in rainbow trout, Oncorhynchus mykiss (Walbaum). JOURNAL OF FISH DISEASES 2005; 28:173-180. [PMID: 15752278 DOI: 10.1111/j.1365-2761.2005.00614.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Two trials were designed to quantify the effect of feeding ratio and fish size on the cohabitation transmission of Loma salmonae, the causative agent of microsporidial gill disease (MGD) in salmonids, Oncorhynchus spp. To evaluate the effect of feeding ratio on disease onset, groups of 45 rainbow trout, O. mykiss (Walbaum) (RBT), were fed daily at 1% (low), 2% (medium) or 4% (high) of the fish biomass in the tank. There were three tanks at each feeding level: two tanks were exposed to the pathogen and one was a control. For the second objective, 300 RBT were separated into seven tanks so that the weight classifications were small (17-23 g), medium (32-38 g) and large (57-63 g). Each size class was done in duplicate with one control tank containing medium-sized fish. Separately for each trial, on day 0 post-exposure (PE) five highly infectious RBT were added to each tank (not including the control tanks) to begin the cohabitation exposure period. Beginning on day 21 PE and continuing biweekly until days 70 and 77 PE for the feeding and fish size trials, respectively, each fish was evaluated for visible branchial xenomas to determine disease onset time. Using survival analysis, the survival curves for the low, medium and high feedings were not significantly different from each other. However, there were significant differences amongst the small, medium and large weight classes in the size trial. The median numbers of days to the development of branchial xenomas was 31, 38 and 42 for small, medium and large size fish, respectively. On any given day, a medium or large sized fish had a hazard ratio for developing branchial xenomas of 0.66 and 0.63, respectively, compared with a small fish. In addition to host species and host strain differences, fish size is now considered a host risk factor for the development of MGD.
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Affiliation(s)
- J A Becker
- Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
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76
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Kucerova Z, Moura H, Visvesvara GS, Leitch GJ. Differences between Brachiola (Nosema) algerae isolates of human and insect origin when tested using an in vitro spore germination assay and a cultured cell infection assay. J Eukaryot Microbiol 2005; 51:339-43. [PMID: 15218704 DOI: 10.1111/j.1550-7408.2004.tb00577.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Brachiola (Nosema) algerae is a microsporidian species generally believed to be an intracellular parasite of insects, especially mosquitoes. However, both mosquito and human isolates have been shown to infect mammalian cells. The present study was undertaken to determine if spores of two insect and two human isolates of B. algerae cultured at 30 degrees C and 37 degrees C differed in their ability to germinate and infect cultured green monkey kidney cells at these two temperatures. Spores from all four isolates exhibited an optimum pH of 9.5 for germination. Mercury (Hg2+) inhibited germination of all isolates equally. Germination of spores from all four isolates was significantly greater when the parasite was cultured at 30 degrees C than when cultured at 37 degrees C. However, spores from the insect isolates cultivated at 30 degrees C or 37 degrees C infected significantly fewer mammalian cells at 37 degrees C than did spores from the human isolates under the same conditions. Thus, there is no correlation between the effects of temperature on the germination and the infectivity of an isolate. In addition, while exposure of B. algerae to 37 degrees C has been reported to cause spore dysmorphism, we failed to observe any consistent ultrastructural changes that explained the greater infectivity of the human isolates at 37 degrees C.
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Affiliation(s)
- Zuzana Kucerova
- Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia 30310, USA
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77
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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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78
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Leiro J, Cano E, Ubeira FM, Orallo F, Sanmartín ML. In vitro effects of resveratrol on the viability and infectivity of the microsporidian Encephalitozoon cuniculi. Antimicrob Agents Chemother 2004; 48:2497-501. [PMID: 15215100 PMCID: PMC434200 DOI: 10.1128/aac.48.7.2497-2501.2004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidians of the genus Encephalitozoon are an important cause of disease in immunocompromised patients, and there are currently no completely effective treatments. The present study investigated the viability and infectivity of spores of Encephalitozoon cuniculi that had been exposed to resveratrol (RESV), a natural phytoalexin found in grapes and red wine. RESV at 50 microM showed significant sporicidal activity, and at 10 to 50 microM it reduced the capacity of the spores to infect dog kidney epithelial cells of the MDCK line. At 10 microM RESV also significantly inhibited intracellular development of the parasite, without affecting host cell viability. These results suggest that RESV may be useful in the treatment of Encephalitozoon infections.
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Affiliation(s)
- José Leiro
- Laboratorio de Parasitología, Instituto de Investigación y Análisis Alimentarios, Universidad de Santiago de Compostela, C/Constantino Candeira s/n, 15782 Santiago de Compostela, Spain.
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79
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Terry RS, MacNeil C, Dick JTA, Smith JE, Dunn AM. Resolution of a taxonomic conundrum: an ultrastructural and molecular description of the life cycle of Pleistophora mulleri (Pfeiffer 1895; Georgevitch 1929). J Eukaryot Microbiol 2004; 50:266-73. [PMID: 15132170 DOI: 10.1111/j.1550-7408.2003.tb00133.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The classification of a microsporidian parasite observed in the abdominal muscles of amphipod hosts has been repeatedly revised but still remains inconclusive. This parasite has variable spore numbers within a sporophorous vesicle and has been assigned to the genera Glugea, Pleistophora, Stempellia, and Thelohania. We used electron microscopy and molecular evidence to resolve the previous taxonomic confusion and confirm its identification as Pleistophora mulleri. The life cycle of P. mulleri is described from the freshwater amphipod host Gammarus duebeni celticus. Infection appeared as white tubular masses within the abdominal muscle of the host. Light and transmission electron microscope examination revealed the presence of an active microsporidian infection that was diffuse within the muscle block with no evidence of xenoma formation. Paucinucleate merogonial plasmodia were surrounded by an amorphous coat immediately external to the plasmalemma. The amorphous coat developed into a merontogenetic sporophorous vesicle that was present throughout sporulation. Sporogony was polysporous resulting in uninucleate spores, with a bipartite polaroplast, an anisofilar polar filament and a large posterior vacuole. SSU rDNA analysis supported the ultrastructural evidence clearly placing this parasite within the genus Pleistophora. This paper indicates that Pleistophora species are not restricted to vertebrate hosts.
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80
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Reetz J, Wiedemann M, Aue A, Wittstatt U, Ochs A, Thomschke A, Manke H, Schwebs M, Rinder H. Disseminated lethal Encephalitozoon cuniculi (genotype III) infections in cotton-top tamarins (Oedipomidas oedipus)--a case report. Parasitol Int 2004; 53:29-34. [PMID: 14984833 DOI: 10.1016/j.parint.2003.10.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2003] [Accepted: 10/07/2003] [Indexed: 11/19/2022]
Abstract
For the first time, Encephalitozoon (E.) cuniculi genotype III ('dog strain') was verified in two cotton-top tamarins (Oedipomidas oedipus) by light microscopy, immunohistochemistry, electron microscopy, PCR and sequencing. The animals had a disseminated lethal infection with this protist. In earlier reports, genotype III had been found only in domestic dogs, man, emperor tamarins (Saguinus imperator) and golden lion tamarins (Leontopithecus rosalia). This investigation establishes now that the 'dog strain' can occur in cotton-top tamarins too. This is further evidence for the zoonotic potential of E. cuniculi. Furthermore, free E. cuniculi spores were identified also in blood vessels of several tissues. These findings indicate that during a disseminated infection E. cuniculi spores can occur in peripheral blood, too. We propose that blood should also be included in the investigations for the detection of microsporidia, so that a possible disseminated course of an infection can be detected.
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Affiliation(s)
- Jochen Reetz
- Federal Institute for Risk Assessment, Diedersdorfer Weg 1, 12277 Berlin, Germany.
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81
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Li X, Tate KW, Dunbar LA, Huang B, Atwill ER. Efficiency for recovering Encephalitozoon intestinalis spores from waters by centrifugation and immunofluorescence microscopy. J Eukaryot Microbiol 2004; 50 Suppl:579-80. [PMID: 14736170 DOI: 10.1111/j.1550-7408.2003.tb00637.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xunde Li
- University of California-Davis, School of Veterinary Medicine, Tulare, CA 93274, USA.
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Abstract
The N-terminal actin-binding domain of alpha-actinin is connected to the C-terminal EF-hands by a rod domain. Because of its ability to form dimers, alpha-actinin can cross-link actin filaments in muscle cells as well as in nonmuscle cells. In the prototypic alpha-actinins, the rod domain contains four triple helical bundles, or so-called spectrin repeats. We have found some atypical alpha-actinins in early diverging organisms, such as protozoa and yeast, where the rod domain contains one and two spectrin repeats, respectively. This implies that the four repeats present in modern alpha-actinins arose after two consecutive intragenic duplications from an alpha-actinin with a single repeat. Further, the evolutionary gene tree of alpha-actinins shows that the appearance of four distinct alpha-actinin isoforms may have occurred after the vertebrate-invertebrate split. The topology of the tree lends support to the hypothesis that two rounds (2R) of genome duplication occurred early in the vertebrate radiation. The phylogeny also considers these atypical isoforms as the most basal to alpha-actinins of vertebrates and other eukaryotes. The analysis also positioned alpha-actinin of the fungi Encephalitozoo cuniculi close to the protozoa, supporting the suggestion that microsporidia are early eukaryotes. Because alpha-actinin is considered the basal member of the spectrin family, our studies will improve the understanding of the origin and evolution of this superfamily.
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Affiliation(s)
- Ana Virel
- Department of Biochemistry, Umeå University, SE-901-87 Umeå, Sweden
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83
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Abstract
In this brief review, literature references are given to researches--involving diverse species of protists--that support the author's firm conviction that the biological world of today absolutely requires the presence of numerous of these generally small and unicelled organisms if it is to survive. Examples supplied come from areas within the field of protistology sensu lato as widely separated as basic phycological research on photosynthesis and protozoological/medical/biomedical investigations on malaria and other pathogens of human beings. Emphasis is primarily on the most relevant works of the past 10-15 years, although historically highly significant papers of older vintage require at least indirect--and occasionally direct--citation.
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84
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Lobo ML, Teles A, da Cunha MB, Henriques J, Lourenço AM, Antunes F, Matos O. Microsporidia Detection in Stools from Pets and Animals from the Zoo in Portugal: A Preliminary Study. J Eukaryot Microbiol 2003; 50 Suppl:581-2. [PMID: 14736171 DOI: 10.1111/j.1550-7408.2003.tb00638.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Maria Luisa Lobo
- Instituto de Higiene e Medicina Tropical/Unidade de Protozoários Oportunistas/VIH e outras Protozooses/UPMM, Rua da Junqueira, 96 1349-008 Lisboa, Portugal.
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85
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Lewis NL, Francis IC, Hawkins GS, Coroneo MT. Bilateral microsporidial keratoconjunctivitis in an immunocompetent non-contact lens wearer. Cornea 2003; 22:374-6. [PMID: 12792484 DOI: 10.1097/00003226-200305000-00018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To describe an immunocompetent male with bilateral microsporidial keratoconjunctivitis who responded to treatment with albendazole, propamidine, and fumagillin. METHODS Corneal and conjunctival epithelial scrapings from a man with bilateral keratoconjunctivitis previously treated with topical corticosteroids were evaluated by Gram stain and by fluorescence microscopy. RESULTS Gram stain and fluorescence microscopy of corneal epithelial scraping revealed organisms characteristic of microsporidia. Results of human immunodeficiency virus antibody testing were reported as nonreactive. Symptoms of ocular discomfort and clinical signs of keratoconjunctivitis resolved after five weeks of treatment that included systemic albendazole and topical propamidine isethionate 0.1% and fumagillin bicyclohexylammonium salt. A follow-up conjunctival scraping failed to detect any residual organisms 2 weeks after cessation of all treatment. CONCLUSION Microsporidial ocular infection occurred in an immunocompetent non-contact lens wearer. Microsporidial keratoconjunctivitis should be considered in any individual with atypical multifocal diffuse epithelial keratitis, regardless of immune status or recent history of contact lens wear.
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Affiliation(s)
- Noni L Lewis
- Department of Opthalmology, The Prince of Wales Hospital, University of New South Wales, Randwick, Sydney.
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86
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Moura H, Ospina M, Woolfitt AR, Barr JR, Visvesvara GS. Analysis of four human microsporidian isolates by MALDI-TOF mass spectrometry. J Eukaryot Microbiol 2003; 50:156-63. [PMID: 12836871 DOI: 10.1111/j.1550-7408.2003.tb00110.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Spores of four species of microsporidia isolated from humans were analyzed by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) and specific biomarkers were found for each. The microsporidia analyzed included three species, Encephalitozoon cuniculi, Encephalitozoon hellem, and Encephalitozoon intestinalis and the fourth organism is the recently described Brachiola algerae. Whole spores, spore shells, and soluble fractions were applied directly to the MALDI target without further purification steps. MALDI-TOF MS analysis of both whole spores and soluble fractions of the four isolates revealed a group of unique, characteristic, and reproducible spectral markers in the mass range of 2,000-8,000 Da. Statistical analysis of the averaged centroided masses uncovered two distinct sets of unique peptides or biomarkers, one originated from whole spores and the other from soluble fractions, that can differentiate the four microsporidian species studied. MALDI-TOF MS analysis of whole organisms is a rapid, sensitive, and specific option to characterize microsporidian isolates and has the potential for several applications in parasitology.
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Affiliation(s)
- Hercules Moura
- Atlanta Research and Education Foundation, Rio de Janeiro, Brazil.
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87
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Abstract
Structural diversity of fish microsporidian life cycle stages and of the host-parasite interface is reviewed. In the infected cell of the fish host, microsporidia may either cause serious degradation of the cytoplasm and demise of the cell, or they may elicit host cell hypertrophy, producing a parasite-hypertrophic host cell complex, the xenoma. The structure of the xenoma and of its cell wall may differ according to the genus of the parasite, and seems to express properties of the parasite rather than those of the host. In merogony, the parasite cell surface interacts with the host cell in diverse ways, the most conspicuous being the production of thick envelopes of different types. Sporogony stages reveal different types of walls or membranes encasing the sporoblasts and later the spores and these envelopes may be of host or parasite origin. Nucleospora differs from all other fish microsporidia by its unique process of sporogony. Except for the formation of conspicuous xenomas, there are no essentially different structures in fish-infecting microsporidia compared with microsporidia from other hosts. Although the structures associated with the development of fish microsporidia cannot be attributed importance in tracing the phylogeny, they are relevant for practical determination and assessing the relation to the host. The possibility of the existence of an intermediate host is discussed. Higher-level classification of Microsporidia is briefly discussed and structure and evolutionary rates in microsporidian rDNA are reviewed. Discussion of rDNA molecular phylogeny of fish-infecting microsporidia is followed by classification of these parasites. Most form a rather cohesive clade. Outside this clade is the genus Nucleospora, separated at least at the level of Order. Within the main clade, however, there are six species infecting hosts other than fish. Based on data available for analysis, a tentative classification of fish-infecting microsporidia into five groups is proposed. Morphologically defined groups represent families, others are referred to as clades. Group 1, represented by family Pleistophoridae, includes Pleistophora, Ovipleistophora and Heterosporis; Vavraia and Trachipleistophora infect non-fish hosts. Group 2, represented by family Glugeidae, is restricted to genus Glugea and Tuzetia weidneri from crustaceans. Group 3 comprises three clades: Loma and a hyperparasitic microsporidian from a myxosporean; Ichthyosporidium and Pseudoloma clade and the Loma acerinae clade. For the latter species a new genus has to be established. Group 4 contains two families, Spragueidae with the genus Spraguea and Tetramicridae with genera Microgemma and Tetramicra, and the Kabatana and Microsporidium seriolae clade. Group 5 is represented by the family Enterocytozoonidae with the genus Nucleospora and mammal-infecting genus Enterocytozoon.
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Affiliation(s)
- Jirí Lom
- Institute of Parasitology, Academy of Sciences of the Czech Republic, Branisovská 31, 370 05 Ceské Budejovice, Czech Republic.
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88
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Goodgame R. Emerging Causes of Traveler's Diarrhea: Cryptosporidium, Cyclospora, Isospora, and Microsporidia. Curr Infect Dis Rep 2003; 5:66-73. [PMID: 12525293 DOI: 10.1007/s11908-003-0067-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Travel is a risk factor for acquiring infection with a spore-forming protozoa: Cryptosopridium, Cyclospora, Microsporidia, and Isospora. Certain travel destinations have a high disease burden and intense exposure. Patients present with persistent diarrhea and a history of recent travel to a developing country in the tropics. Very mild infections may be underdiagnosed and may cause typical traveler's diarrhea. In a patient with a history of travel and persistent diarrhea unresponsive to the usual antibiotic and antidiarrhea treatment, stool studies for all four of these protozoa infections should be performed. If immune status is normal and the disease is mild, symptomatic therapy may suffice. Effective treatment is available for Cyclospora, Microsporidia, and Isospora.
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Affiliation(s)
- Richard Goodgame
- Baylor College of Medicine, Room BCMD 525D, Houston, TX 77030, USA.
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89
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Svedhem V, Lebbad M, Hedkvist B, Del Aguila C, Hedman P, Larsson R, Navajas R, Aust-Kettis A. Disseminated infection with encephalitozoon intestinalis in AIDS patients: report of 2 cases. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 2003; 34:703-5. [PMID: 12374372 DOI: 10.1080/00365540210147598] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Microsporidiosis must be regarded as a late opportunistic infection when HIV is advanced. In this article we describe 2 cases of disseminated infection with Encephalitozoon intestinalis. The first case had a local intestinal infection for > 1 y before it disseminated and microsporidia were found intracellularly in sputum. In the second case, spores were initially found in conjunctival cells, sinus lavage, sputum and urine. This patient had clinical symptoms and radiological findings from the central nervous system. Signs of cerebral lymphoma developed after treatment of the opportunistic microsporidial infection.
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Affiliation(s)
- Veronica Svedhem
- Department of Infectious Diseases, Karolinska Institutet, Karolinska Hospital, Stockholm, Sweden.
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90
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Hester JD, Varma M, Bobst AM, Ware MW, Lindquist HDA, Schaefer FW. Species-specific detection of three human-pathogenic microsporidial species from the genus Encephalitozoon via fluorogenic 5' nuclease PCR assays. Mol Cell Probes 2002; 16:435-44. [PMID: 12490145 DOI: 10.1006/mcpr.2002.0442] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study describes fluorogenic 5' nuclease PCR assays suitable for rapid, sensitive, high-throughput detection of the human-pathogenic microsporidial species Encephalitozoon hellem, E. cuniculi and E.intestinalis. The assays utilize species-specific primer sets and a genus-specific dual fluorescent-labeled probe that anneals to a region within the Encephalitozoon 16S rRNA gene. The assay design theoretically permits the probe to be used either with one set of primers for species-level determination or with a combination of all three primer sets for a genus-level screening of samples. The linear range of all three species-specific calibration curves that were developed using serial ten-fold dilutions of genomic DNA isolated from hemacytometer counted spores was determined to be between 10(4) and 10(-1) spores per PCR sample. The coefficients of variation were < or =5.2% over the entire 5-log span of each calibration curve. When DNA isolated from flow cytometric enumerated spores from each of the three Encephalitozoon species was used to evaluate the quantitative capability of the species' respective calibration curves, the results from 34 out of 36 (94%) samples were within 2 standard deviations. The species-specificity of each assay was confirmed using DNA isolated from 10(4) spores from each of the other two Encephalitozoon species as well as DNA extracted from numerous other protozoa, algae and bacteria.
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Affiliation(s)
- J D Hester
- National Exposure Research Laboratory, United States Environmental Protection Agency, Cincinnati, OH 45268, USA
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