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Journal of Invertebrate Pathology Jun 2024The genus Vairimorpha was proposed for several species of Nosema in 1976 (Pilley, 1976), almost 70 years after Nosema apis Zander (Zander, 1909). Tokarev and colleagues...
The genus Vairimorpha was proposed for several species of Nosema in 1976 (Pilley, 1976), almost 70 years after Nosema apis Zander (Zander, 1909). Tokarev and colleagues proposed the redefinition of 17 microsporidian species in four genera, Nosema, Vairimorpha, Rugispora, and Oligosporidium, based on phylogenetic trees of two genetic markers (SSU rRNA and RPB1) (Tokarev et al., 2020). Several issues should invalidate this new classification, leading to the synonymization of Vairimorpha within Nosema.
PubMed: 38852837
DOI: 10.1016/j.jip.2024.108146 -
Animals : An Open Access Journal From... Aug 2023Microsporidia are widely spread obligate intracellular fungal pathogens from vertebrate and invertebrate organisms, mainly transmitted by contaminated food and water....
Microsporidia are widely spread obligate intracellular fungal pathogens from vertebrate and invertebrate organisms, mainly transmitted by contaminated food and water. This study aims to detect the presence of major human-pathogenic microsporidia, i.e., , , , and , in the gastrointestinal tract of commercially harvested marine fish from Mediterranean coast of the Comunidad Valenciana, Eastern Spain. A total of 251 fish, 138 farmed fish and 113 wild fish from commercial fishing were tested by SYBR Green real-time PCR, enabling the simultaneous detection of the four targeted species. was found in 1.45% of farmed fish and 7.96% of wild fish, while Enterocytozoonidae was detected in 2.90% and 18.58% of farmed and wild fish, respectively. was not detected in any of the analyzed specimens. To the authors' knowledge, this is the first report of in fish, particularly in marine fish. Although the role of fish in these species' epidemiology remains unknown, this finding points out a potential public health risk linked to fish consumption. Further studies are necessary to characterize these microsporidia in fish hosts better and to elucidate their epidemiological role.
PubMed: 37627464
DOI: 10.3390/ani13162673 -
Microbiology Spectrum Feb 2024Microsporidia are intracellular fungus-like pathogens and the infection symptoms include recurrent diarrhea and systematic inflammations. The major infection route of...
Microsporidia are intracellular fungus-like pathogens and the infection symptoms include recurrent diarrhea and systematic inflammations. The major infection route of microsporidia is the digestive tract. Since microsporidia are hard to fully eliminate, the interactions and persistence of the pathogen within epithelium may modulate host susceptibility to digestive disorders. In this study, both and infection models were applied. The alterations of epithelial barrier integrity, permeability, and tight junction proteins after microsporidia infection were assessed on MDCK/Caco-2 monolayers. The fecal intestinal microbiota and tissue alterations after microsporidia infection were assessed on C57BL/6 mice. Moreover, the susceptibility to develop dextran sulfate sodium (DSS)-induced inflammatory bowel diseases (IBDs) was also analyzed by the murine infection model. The results demonstrated that microsporidia infection increased epithelium permeability, weakened wound healing capability, and destructed tight junction protein zonula occludens-1. Microsporidia infection also dysregulates intestinal microbiota. These impairing effects of microsporidia increased host vulnerability to develop enteritis as shown by the murine model of DSS-induced IBD. Our study is the first to elucidate molecular mechanisms of the damaging effects of microsporidia on host epithelium and pointed out the cryptic threats of latent microsporidia infection to public health as reflected by the increased chances of developing more severe diseases.IMPORTANCEMicrosporidia are widely present in nature and usually cause latent and persistent infections in hosts. Given the fact that the digestive tract is the major infection route, it is of great importance to explore the consequences of microsporidia infection on the intestinal epithelial barrier and the risks to the host. In this study, we demonstrated the destructing effects of microsporidium infection on epithelial barriers manifested as increased epithelial permeability, weakened wound healing ability, and disrupted tight junctions. Moreover, microsporidia made the host more susceptible to dextran sulfate sodium-induced inflammatory bowel disease. These findings provide new evidence for us to better understand and develop novel strategies for microsporidia prevention and disease control.
Topics: Humans; Animals; Mice; Colitis; Caco-2 Cells; Microsporidia; Dextran Sulfate; Intestinal Mucosa; Mice, Inbred C57BL; Inflammatory Bowel Diseases; Microsporidiosis; Disease Models, Animal
PubMed: 38149855
DOI: 10.1128/spectrum.03610-23 -
Diseases of Aquatic Organisms May 2024A novel microsporidium was observed in wild swamp guppies Micropoecilia picta from Levera Pond within Levera National Park Grenada, West Indies. Initial observations...
A novel microsporidium was observed in wild swamp guppies Micropoecilia picta from Levera Pond within Levera National Park Grenada, West Indies. Initial observations indicated similarity with Pseudoloma neurophilia, an important pathogen in zebrafish Danio rerio. P. neurophilia exhibit broad host specifity, including members of the family Poecillidae, and both parasites infect the central nervous system. However, spore morphology and molecular phylogeny based on rDNA showed that the swamp guppy microsporidium (SGM) is distinct from P. neurophilia and related microsporidia (Microsporidium cerebralis and M. luceopercae). Spores of the SGM were smaller than others in the clade (3.6 µm long). Differences were also noted in histology; the SGM formed large aggregates of spores within neural tissues along with a high incidence of numerous smaller aggregates and single spores within the surface tissue along the ventricular spaces that extended submeninx, whereas P. neurophilia and M. cerebralis infect deep into the neuropile and cause associated lesions. Analysis of small subunit ribosomal DNA sequences showed that the SGM was <93% similar to these related microsporidia. Nevertheless, one of 2 commonly used PCR tests for P. neurophilia cross reacted with tissues infected with SGM. These data suggest that there could be other related microsporidia capable of infecting zebrafish and other laboratory fishes that are not being detected by these highly specific assays. Consequently, exclusive use of these PCR tests may not accurately diagnose other related microsporidia infecting animals in laboratory and ornamental fish facilities.
Topics: Animals; Fish Diseases; Microsporidia; Microsporidiosis; Phylogeny; Poecilia; Grenada
PubMed: 38813854
DOI: 10.3354/dao03789 -
BioRxiv : the Preprint Server For... Aug 2023Microsporidia are eukaryotic, obligate intracellular parasites that infect a wide range of hosts, leading to health and economic burdens worldwide. Microsporidia use an...
Microsporidia are eukaryotic, obligate intracellular parasites that infect a wide range of hosts, leading to health and economic burdens worldwide. Microsporidia use an unusual invasion organelle called the polar tube (PT), which is ejected from a dormant spore at ultra-fast speeds, to infect host cells. The mechanics of PT ejection are impressive. microsporidia spores (3-4 m in size) shoot out a 100-nm-wide PT at a speed of 300 m/sec, creating a shear rate of 3000 sec. The infectious cargo, which contains two nuclei, is shot through this narrow tube for a distance of ~60-140 m (Jaroenlak et al., 2020) and into the host cell. Considering the large hydraulic resistance in an extremely thin tube and the low-Reynolds-number nature of the process, it is not known how microsporidia can achieve this ultrafast event. In this study, we use Serial Block-Face Scanning Electron Microscopy to capture 3-dimensional snapshots of spores in different states of the PT ejection process. Grounded in these data, we propose a theoretical framework starting with a systematic exploration of possible topological connectivity amongst organelles, and assess the energy requirements of the resulting models. We perform PT firing experiments in media of varying viscosity, and use the results to rank our proposed hypotheses based on their predicted energy requirement. We also present a possible mechanism for cargo translocation, and quantitatively compare our predictions to experimental observations. Our study provides a comprehensive biophysical analysis of the energy dissipation of microsporidian infection process and demonstrates the extreme limits of cellular hydraulics.
PubMed: 36711805
DOI: 10.1101/2023.01.17.524456 -
Frontiers in Microbiology 2023and are etiological agents of enteric diseases characterized by diarrhea that can progress to chronicity in humans, especially in children and in immunocompromised...
and are etiological agents of enteric diseases characterized by diarrhea that can progress to chronicity in humans, especially in children and in immunocompromised patients. This study aims to assess the genetic pattern of and detected in vegetables and fruits commercialized in Maputo markets, Mozambique and determine their public health importance. Eight study points were sampled: a farmer zone, a wholesale, four retail markets, and two supermarkets in Maputo city, where eight types of horticultural products were purchased. Using nested-PCR methods, 2.8% (9/321) and 1.3% (4/321) of samples monitored were positive for and , respectively. Based on the analysis of the β-giardin and ITS rRNA sequences of and detected, respectively, four different sequences of (three novel sequences: BgMZ1, BgMZ2, and BgMZ3, and one known sequence) all from assemblage B and three genotypes of (two novel sequences: EbMZ4 and EbMZ5, and one known sequence: KIN-1) from group 1. These microorganisms were found and characterized for the first time in horticultural products in Maputo markets. All identified and display high genetic similarity within their β-giardin and ITS rRNA sequences, respectively, having been clustered into assemblages and genotypes with high zoonotic transmission potential. Our study may represent a relevant step in the understanding of these intestinal pathogens in association with fresh vegetables and fruits for human consumption, for a better and broader "One Health" approach.
PubMed: 37601378
DOI: 10.3389/fmicb.2023.1223151 -
Molecular and Biochemical Parasitology Jun 2024Pebrine disease, caused by Nosema bombycis (N. bombycis), is the most important pathogen known to the silk industry. Historical evidence from several countries shows... (Review)
Review
Pebrine disease, caused by Nosema bombycis (N. bombycis), is the most important pathogen known to the silk industry. Historical evidence from several countries shows that the outbreaks of pebrine disease have largely caused the decline of the sericulture industry. Prevention is the first line to combat pebrine as a deadly disease in silkworm; however, no effective treatment has yet been presented to treat the disease. Many different methods have been used for detection of pebrine disease agent. This review focuses on the explanation and comparison of these methods, and describes their advantages and/or disadvantages. Also, it highlights the ongoing advances in diagnostic methods for N. bombycis that could enable efforts to halt this microsporidia infection. The detection methods are categorized as microscopic, immunological and nucleic acid-based approaches, each with priorities over the other methods; however, the suitability of each method depends on the available equipment in the laboratory, the mass of infection, and the speed and sensitivity of detection. The accessibility and economic efficiency are compared as well as the speed and the sensitivity for each method. Although, the light microscopy is the most common method for detection of N. bombycis, qPCR is the most preferred method for large data based on speed and sensitivity as well as early detection ability.
PubMed: 38908801
DOI: 10.1016/j.molbiopara.2024.111645 -
Cell May 2024FMS-related tyrosine kinase 3 ligand (FLT3L), encoded by FLT3LG, is a hematopoietic factor essential for the development of natural killer (NK) cells, B cells, and...
FMS-related tyrosine kinase 3 ligand (FLT3L), encoded by FLT3LG, is a hematopoietic factor essential for the development of natural killer (NK) cells, B cells, and dendritic cells (DCs) in mice. We describe three humans homozygous for a loss-of-function FLT3LG variant with a history of various recurrent infections, including severe cutaneous warts. The patients' bone marrow (BM) was hypoplastic, with low levels of hematopoietic progenitors, particularly myeloid and B cell precursors. Counts of B cells, monocytes, and DCs were low in the patients' blood, whereas the other blood subsets, including NK cells, were affected only moderately, if at all. The patients had normal counts of Langerhans cells (LCs) and dermal macrophages in the skin but lacked dermal DCs. Thus, FLT3L is required for B cell and DC development in mice and humans. However, unlike its murine counterpart, human FLT3L is required for the development of monocytes but not NK cells.
Topics: Animals; Female; Humans; Male; Mice; B-Lymphocytes; Bone Marrow; Cell Lineage; Dendritic Cells; Hematopoiesis; Hematopoietic Stem Cells; Killer Cells, Natural; Langerhans Cells; Membrane Proteins; Monocytes; Skin; Mice, Inbred C57BL
PubMed: 38701783
DOI: 10.1016/j.cell.2024.04.009 -
Malaria Journal Mar 2024Recently, bacterial endosymbiont, including Wolbachia and Microsporidia were found to limit the infection of Anopheles mosquitoes with Plasmodium falciparum. This study...
BACKGROUND
Recently, bacterial endosymbiont, including Wolbachia and Microsporidia were found to limit the infection of Anopheles mosquitoes with Plasmodium falciparum. This study aimed to investigate the natural presence of key transmission-blocking endosymbionts in Anopheles gambiae and Anopheles coluzzii in Southern Benin.
METHODS
The present study was conducted in seven communes (Cotonou, Porto-Novo, Aguégués, Ifangni, Pobè Athiémé, and Grand-Popo) of Southern Benin. Anopheles were collected using indoor/outdoor Human Landing Catches (HLCs) and Pyrethrum Spray Catches (PSCs). Following morphological identification, PCR was used to identify An. gambiae sensu lato (s.l.) to species level and to screen for the presence of both Wolbachia and Microsporidia. Plasmodium falciparum sporozoite infection was also assessed using ELISA.
RESULTS
Overall, species composition in An. gambiae s.l. was 53.7% An. coluzzii, while the remainder was An. gambiae sensu stricto (s.s.). Combined data of the two sampling techniques revealed a mean infection prevalence with Wolbachia of 5.1% (95% CI 0.90-18.6) and 1.3% (95% CI 0.07-7.8) in An. gambiae s.s. and An. coluzzii, respectively. The mean infection prevalence with Microsporidia was 41.0% (95% CI 25.9-57.8) for An. gambiae s.s. and 57.0% (95% CI 45.4-67.9) for An. coluzzii. Wolbachia was only observed in Ifangni, Pobè, and Cotonou, while Microsporidia was detected in all study communes. Aggregated data for HLCs and PSCs showed a sporozoite rate (SR) of 0.80% (95% CI 0.09-2.87) and 0.69% (95% CI 0.09-2.87) for An. gambiae and An. coluzzii, respectively, with a mean of 0.74% (95% CI 0.20-1.90). Of the four individual mosquitoes which harboured P. falciparum, none were also infected with Wolbachia and one contained Microsporidia.
CONCLUSIONS
The present study is the first report of natural infections of field-collected An. gambiae s.l. populations from Benin with Wolbachia and Microsporidia. Sustained efforts should be made to widen the spectrum of bacteria identified in mosquitoes, with the potential to develop endosymbiont-based control tools; such interventions could be the game-changer in the control of malaria and arboviral disease transmission.
Topics: Animals; Humans; Benin; Anopheles; Wolbachia; Cross-Sectional Studies; Mosquito Vectors; Malaria, Falciparum; Pyrethrins; Sporozoites
PubMed: 38468292
DOI: 10.1186/s12936-024-04906-1 -
Parasitology Research Dec 2023Nosema bombycis, an obligate intracellular parasite, is a single-celled eukaryote known to infect various tissues of silkworms, leading to the manifestation of pebrine....
Nosema bombycis, an obligate intracellular parasite, is a single-celled eukaryote known to infect various tissues of silkworms, leading to the manifestation of pebrine. Trehalase, a glycosidase responsible for catalyzing the hydrolysis of trehalose into two glucose molecules, assumes a crucial role in thermal stress tolerance, dehydration, desiccation stress, and asexual development. Despite its recognized importance in these processes, the specific role of trehalase in N. bombycis remains uncertain. This investigation focused on exploring the functions of trehalase 3 in N. bombycis (NbTre3). Immunofluorescence analysis of mature (dormant) spores indicated that NbTre3 primarily localizes to the spore membrane or spore wall, suggesting a potential involvement in spore germination. Reverse transcription-quantitative polymerase chain reaction results indicated that the transcriptional level of NbTre3 peaked at 6 h post N. bombycis infection, potentially contributing to energy storage for proliferation. Throughout the life cycle of N. bombycis within the host cell, NbTre3 was detected in sporoplasm during the proliferative stage rather than the sporulation stage. RNA interference experiments revealed a substantial decrease in the relative transcriptional level of NbTre3, accompanied by a certain reduction in the relative transcriptional level of Nb16S rRNA. These outcomes suggest that NbTre3 may play a role in the proliferation of N. bombycis. The application of the His pull-down technique identified 28 proteins interacting with NbTre3, predominantly originating from the host silkworm. This finding implies that NbTre3 may participate in the metabolism of the host cell, potentially utilizing the host cell's energy resources.
Topics: Animals; Trehalase; Spores, Fungal; Nosema; Microsporidiosis; Bombyx
PubMed: 38112902
DOI: 10.1007/s00436-023-08082-0