Tritrichomonas Muris Research Articles

Tritrichomonas muris sensitizes the intestinal epithelium to doxorubicin-induced apoptosis.

Doxorubicin (DXR) is a widely used chemotherapy drug that can induce severe intestinal mucositis. While the influence of gut bacteria on DXR-induced damage has been documented, the role of eukaryotic commensals remains unexplored. We discovered Tritrichomonas muris (Tmu) in one of our mouse colonies exhibiting abnormal tuft cell hyperplasia, prompting an investigation into its impact on DXR-induced intestinal injury. Mice from Tmu-colonized and Tmu-excluded facilities were injected with DXR, and tissue morphology and gene expression were evaluated at acute injury (6 h) and peak regeneration (120 h) phases. Contrary to previous reports, DXR did not significantly alter villus height, crypt depth, or crypt density in any mice. However, we did observe apoptosis, measured by cleaved caspase 3 (CC3) staining, in intestinal crypts at 6 h post-DXR that was significantly higher in mice colonized by Tmu. Interestingly, while DXR did not alter the expression of active and facultative intestinal stem cell (ISC) marker genes in control mice, it significantly reduced their expression in Tmu + mice. Tmu, but not DXR, is also associated with increased inflammation and expression of the type 2 cytokines IL-5 and IL-13. However, pre-treatment of intestinal organoids with these cytokines is not sufficient to drive elevated DXR-induced apoptosis. These findings highlight the significant influence of commensal microbiota, particularly eukaryotic organisms like Tmu, on intestinal biology and response to chemotherapy, underscoring the complexity of gut microbiota interactions in drug-induced mucositis.

NLRP1B allele 2 does not respond to Val-boro-Pro (VbP) in intestinal epithelial cells

The intestinal mucosa must balance tolerance to commensal microbes and luminal antigens with rapid detection of enteric pathogens in order to maintain homeostasis. This balance is facilitated through the regulation of epithelial layer integrity by innate immune receptors. Certain NOD-like receptors (NLRs) expressed in intestinal epithelial cells, including NLRC4 and NLRP9B, form inflammasomes that protect against pathogens by activating caspase-1 to cause extrusion of infected cells. NLRP1B is a murine NLR encoded by five alleles of a highly polymorphic gene homologous to human NLRP1. NLRP1B forms inflammasomes in response to a variety of pathogens that cause intestinal infections, but it has almost exclusively been studied in immune cells and has not been characterized in cells of the intestinal epithelium. Here, we show that Nlrp1b allele 2 is expressed in ileal and colonic organoids derived for C57BL/6J mice, while the related gene Nlrp1a was not expressed. Nlrp1b was upregulated by interleukin-13 in organoids and by the protozoan Tritrichomonas muris in vivo, suggesting that NLRP1B may be involved in defense against enteric parasites. Surprisingly, while Val-boro-Pro (VbP) activated C57BL/6J-derived bone marrow-derived macrophages, which expressed both Nlrp1a and Nlrp1b, it did not activate intestinal organoids of the same genotype. We furthermore did not detect Nlrp1b in organoids derived from Balb/cJ mice, which express a different allele than the one expressed in C57BL/6J mice. Together, our results suggest that NLRP1B may have an allele-dependent function in murine IECs whose regulation is distinct from that of macrophages, and that the response to VbP might be exclusively driven by NLRP1A in C57BL/6J mice.

Development of Nested Polymerase Chain Reaction with Novel Specific Primers for Detection of Tritrichomonas muris Infection in Laboratory Mice.

A variety of rodent ceca are parasitized by Tritrichomonas muris (T. muris), a flagellated protozoan. To date, there are no ideal methods for the detection of T. muris infections in laboratory mice; thus, new molecular methodologies for its specific detection need to be developed. In this study, using staining and SEM, it was observed that T. muris has a pear-shaped body and contains three anterior flagella. A nested PCR system with novel specific primers was designed based on the conserved regions of the SSU rRNA gene of T. muris. The nested PCR system for T. muris showed good specificity and high sensitivity for at least 100 T. muris trophozoites/mL and 0.1 ng/μL of fecal genomic DNA, which means that 176 trophozoites per gram of mouse feces could be detected. When using this nested PCR system, the detection rate was 18.96% (58/306), which was higher than the detection rate of 14.05% (43/306) detected via smear microscopy in fecal samples from five mouse strains. The sensitivity and specificity of nested PCR in detecting T. muris was found to be 100%, and it demonstrated a 26% increase in diagnostic sensitivity compared to the smear microscopy method in the present study. In conclusion, the nested PCR developed with novel primers based on the SSU rRNA gene of T. muris has good accuracy, specificity, and sensitivity for the detection of T. muris infections in laboratory mice.

Fine structure and molecular characterization of two new parabasalid species that naturally colonize laboratory mice, Tritrichomonas musculus and Tritrichomonas casperi.

Tritrichomonas muris is a common flagellated protist isolated from the cecum of wild rodents. This commensal protist has been shown previously to alter immune phenotypes in laboratory mice. Other trichomonads, referred to as Tritrichomonas musculis and Tritrichomonas rainier, also naturally colonize laboratory mice and cause immune alterations. This report formally describes two new trichomonads, Tritrichomonas musculus n. sp., and Tritrichomonas casperi n. sp., at the ultrastructural and molecular level. These two protists were isolated from laboratory mice and were differentiated by their size and the structure of their undulating membrane and posterior flagellum. Analysis at the 18S rRNA and trans-ITS genetic loci supported their designation as distinct species, related to T. muris. To assess the true extent of parabasalid diversity infecting laboratory mice, 135 mice bred at the National Institutes of Health (NIH) were screened using pan-parabasalid primers that amplify the trans-ITS region. Forty-four percent of mice were positive for parabasalids, encompassing a total of eight distinct sequence types. Tritrichomonas casperi and Trichomitus-like protists were dominant. T. musculus and T. rainier were also detected, but T. muris was not. Our work establishes a previously underappreciated diversity of commensal trichomonad flagellates that naturally colonize the enteric cavity of laboratory mice.

Microbiota and environmental health monitoring of mouse colonies by metagenomic shotgun sequencing

Metagenomic next-generation sequencing (mNGS) allows the monitoring of microbiota composition of murine colonies employed for scientific purposes in a single test by assessing the composition of gut microbiome and the detection of pathogens from fecal pellets. In this study, we tested the potential use of mNGS for monitoring both microbiota composition and the presence of pathogens through Environmental Health Monitoring, by using exhaust dust collection filters derived from individually ventilated cages (IVC) systems.mNGS analysis was performed on nucleic acids isolated from filters collecting air from the exhaust of: (1) cages with mice housed in a non-pathogen free facility; (2) animal-free cages with clean chow and bedding from the same facility; (3) cages housing mice from a specific-pathogen free (SPF) facility. mNGS results revealed correspondence between microbiome composition from fecal pellets and filter, including pathogenic bacteria (Helicobacter hepaticus, Helicobacter typhlonius, Chlamydia muridarum, Rodentibacter pneumotropicus, Citrobacter rodentium), intestinal protozoa (Tritrichomonas muris, Spironucleus muris) nematoda (Aspiculuris tetraptera) and eukaryotic parasites (Myocoptes musculinus), present in the colony. Entamoeba muris and Syphacia obvelata were detected in fecal pellets but not in filter. The animal free exhaust dust filter, exposed to clean cages (no mice) placed in the IVC after removal of all mice, exhibited the presence of the same pathogens due to contaminated connecting pipes, confirming the sensitivity of the approach. Conversely, the filter from SPF colony revealed the absence of pathogens.The current use of exhaust dust collection filters in health surveillance requires multiple molecular tests to identify specific pathogens and does not provide information on the colony microbiome. This work provides the proof-of-principle that assaying exhaust dust collection filters by mNGS for microbiota monitoring of laboratory mice is feasible. In its daily application, results suggest the usefulness of the test in SPF facilities, where pathogenic micro-organisms are expected to be absent. mNGS analysis of exhaust dust collection filters allows the analysis of multiple cages, reducing the number of tests required for pathogen detection and corresponding costs, and avoiding the use of sentinel mice.

Evaluation of the inhibitory impact of biosynthesized silver nanoparticles using Bacillus cereus and Chromobacterium violaceum bacteria on some intestinal protozoa.

Nano materials are utilized to improve the performance of some pharmaceuticals and materials, as well as to lessen the collateral damage they cause. The purpose of this study was to look at the effect of silver nanoparticles (AgNPs) produced by bacteria on some trophozoites of intestinal parasites. The silver nanoparticles were synthesized using Bacillus cereus (BAgNPs) and Chromobacterium violaceum (ChAgNPs) bacteria. The AgNPs production was confirmed by several tests and techniques, such as electron microscopy. The results of the analysis showed that the size of these particles was within the range of 21-96.71 nm for both BAgNPs and ChAgNPs. In vitro and in vivo efficacy were tested on some trophozoites of intestinal parasites. The effect of the AgNPs on Entamoeba histolytica trophozoites in culture was significantly higher compared to metronidazole. The highest percentage of inhibition was 70.6% and 76.5% for the particles prepared from B. cereus and C. violaceum without significant differences between the two bacteria, compared to 57.6% inhibition for metronidazole. The in vivo effect of the AgNPs on Giardia lamblia exceeded that of metronidazole and led to the total disappearance of the stages from mice faeces after 3-4 days. Likewise, Tritrichomonas muris numbers were also reduced in infected mice treated with AgNPs, with the highest inhibition rate of 81.3%. From above can concluded these bacterially produced nanoparticles have proven strong efficacy, and it is possible to recommend their use independently after conducting studies on the extent of their effects on the body and proving their safety.

A comprehensive approach for microbiota and health monitoring in mouse colonies using metagenomic shotgun sequencing

BackgroundHealth surveillance of murine colonies employed for scientific purposes aim at detecting unwanted infection that can affect the well-being of animals and personnel, and potentially undermine scientific results. In this study, we investigated the use of a next-generation sequencing (NGS) metagenomic approach for monitoring the microbiota composition and uncovering the possible presence of pathogens in mice housed in specific pathogen-free (SPF) or conventional (non-SPF) facilities.ResultsAnalysis of metagenomic NGS assay through public and free algorithms and databases allowed to precisely assess the composition of mouse gut microbiome and quantify the contribution of the different microorganisms at the species level. Sequence analysis allowed the uncovering of pathogens or the presence of imbalances in the microbiota composition. In several cases, fecal pellets taken from conventional facilities were found to carry gene sequences from bacterial pathogens (Helicobacter hepaticus, Helicobacter typhlonius, Chlamydia muridarum, Streptococcus pyogenes, Rodentibacter pneumotropicus, Citrobacter rodentium, Staphylococcus aureus), intestinal protozoa (Entamoeba muris, Tritrichomonas muris, Spironucleus muris) nematoda (Aspiculuris tetraptera, Syphacia obvelata), eukaryotic parasites (Myocoptes musculinus) and RNA virus (Norwalk virus). Thus, the use of NGS metagenomics can reduce the number of tests required for the detection of pathogens and avoid the use of sentinel mice.ConclusionsIn summary, in comparison with standard approaches, which require multiple types of test, NGS assay can detect bacteria, fungi, DNA and RNA viruses, and eukaryotic parasites from fecal pellets in a single test. Considering the need to protect animal well-being and to improve the success and reproducibility of preclinical studies, this work provides the proof-of-concept that the use of NGS metagenomics for health monitoring of laboratory mice is a feasible and dependable approach, that is able to broaden the current concept of health monitoring of laboratory mice from “pathogen surveillance” to a more inclusive “microbiota surveillance”.

Tumor suppressor p53 regulates intestinal type 2 immunity

The role of p53 in tumor suppression has been extensively studied and well-established. However, the role of p53 in parasitic infections and the intestinal type 2 immunity is unclear. Here, we report that p53 is crucial for intestinal type 2 immunity in response to the infection of parasites, such as Tritrichomonas muris and Nippostrongylus brasiliensis. Mechanistically, p53 plays a critical role in the activation of the tuft cell-IL-25-type 2 innate lymphoid cell circuit, partly via transcriptional regulation of Lrmp in tuft cells. Lrmp modulates Ca2+ influx and IL-25 release, which are critical triggers of type 2 innate lymphoid cell response. Our results thus reveal a previously unrecognized function of p53 in regulating intestinal type 2 immunity to protect against parasitic infections, highlighting the role of p53 as a guardian of immune integrity.

MULTIPLEX POLYMERASE CHAIN REACTION ASSAY FOR THE DETECTION OF FIVE COMMON ENDOPARASITE INFESTATIONS IN LABORATORY RODENTS

Rodent pinworms, Spironucleus muris and Tritrichomonas muris are the endoparasites that should be monitored and excluded from laboratory animal colonies. Nevertheless, traditional diagnostic methods may not efficiently detect and accurately demonstrate the endoparasite infestation status. In this study, we developed a multiplex PCR assay targeting the rRNA genes to simultaneously detect and differentiate five endoparasites, including Syphacia obvelata, Syphacia muris, Aspiculuris tetraptera, Spironucleus muris, and T. muris, as well as a housekeeping gene in feces. The multiplex PCR could identify an equivalent infection of pinworm, Spironucleus muris and T. muris, with a detection limit of as few as 10 copies. Furthermore, dual infections with up to 100-fold differences and triple infections with 10-fold differences in parasite loads can also be detected. In comparison of traditional methods with the multiplex PCR assay, 76 rodents from 11 research colonies and 3 pet shops and additional 27 fecal samples from laboratory rodents were screened for the infestation status of the five endoparasites. The multiplex PCR had higher sensitivity (97.2–100%) and accuracy (99–100%) than those of the traditional antemortem (sensitivity: 83–100%; accuracy: 94–100%) and postmortem methods (sensitivity: 75–100%; accuracy: 92.1–100%). In addition, an early stage of S. obvelata contamination in a SPF laboratory animal colony was also successfully detected by this multiplex PCR assay. This Pinworm/Spironucleus/Tritrichomonas/Actin Multiplex PCR assay should be a powerful tool to screen endoparasite infestations in laboratory colonies without animal sacrifice.

The Taste Receptor TAS1R3 Regulates Small Intestinal Tuft Cell Homeostasis.

Tuft cells are an epithelial cell type critical for initiating type 2 immune responses to parasites and protozoa in the small intestine. To respond to these stimuli, intestinal tuft cells use taste chemosensory signaling pathways, but the role of taste receptors in type 2 immunity is poorly understood. In this study, we show that the taste receptor TAS1R3, which detects sweet and umami in the tongue, also regulates tuft cell responses in the distal small intestine. BALB/c mice, which have an inactive form of TAS1R3, as well as Tas1r3-deficient C57BL6/J mice both have severely impaired responses to tuft cell–inducing signals in the ileum, including the protozoa Tritrichomonas muris and succinate. In contrast, TAS1R3 is not required to mount an immune response to the helminth Heligmosomoides polygyrus, which infects the proximal small intestine. Examination of uninfected Tas1r3−/− mice revealed a modest reduction in the number of tuft cells in the proximal small intestine but a severe decrease in the distal small intestine at homeostasis. Together, these results suggest that TAS1R3 influences intestinal immunity by shaping the epithelial cell landscape at steady-state. ImmunoHorizons, 2020, 4: 23–32.

Gastrointestinal parasitic infection in laboratory rats: a challenge for researchers

Laboratory animals, especially mice and rats, are commonly used in biomedical researches. This study was designed to evaluate the status of gastrointestinal parasites in Wistar rats using parasitological methods. Sixty Wistar rats in different ages which were being maintained conventionally were selected randomly from laboratory animal house. The contents of the gastrointestinal tract of the rats were examined by parasitological methods. All of the rats under study were infected with at least one parasite. Twelve genera of parasites were detected in the rats, the six of which were protozoa including Giardia muris, Entamoeba muris, Blastocystis spp., Eimeria spp., Tritrichomonas muris, and Cryptosporidium spp., and the six other ones were helminths including Hymenolepis nana, Syphacia muris, Syphacia obvelata, Strongyloides ratti, Trichosomoides crassicauda (bladder parasite), and Aspiculuris tetraptera. G. muris showed the highest prevalence rate (96%) followed by T. muris (95%). In addition, the lowest prevalence rate observed in this study was related to S. obvelata, S. ratti, T. crassicauda, and A. tetraptera, all with 1.5% prevalence. Consequently, it is crucial for researchers to monitor laboratory animals by health surveillance programs, essentially emphasizing the good laboratory practice (GLP) to ensure the quality, consistency, and reproducibility of data in their research.

Epithelial cell specific Raptor is required for initiation of type 2 mucosal immunity in small intestine

Intestinal tuft cells are one of 4 secretory cell linages in the small intestine and the source of IL-25, a critical initiator of the type 2 immune response to parasite infection. When Raptor, a critical scaffold protein for mammalian target of rapamycin complex 1 (mTORC1), was acutely deleted in intestinal epithelium via Tamoxifen injection in Tritrichomonas muris (Tm) infected mice, tuft cells, IL-25 in epithelium and IL-13 in the mesenchyme were significantly reduced, but Tm burden was not affected. When Tm infected mice were treated with rapamycin, DCLK1 and IL-25 expression in enterocytes and IL-13 expression in mesenchyme were diminished. After massive small bowel resection, tuft cells and Tm were diminished due to the diet used postoperatively. The elimination of Tm and subsequent re-infection of mice with Tm led to type 2 immune response only in WT, but Tm colonization in both WT and Raptor deficient mice. When intestinal organoids were stimulated with IL-4, tuft cells and IL-25 were induced in both WT and Raptor deficient organoids. In summary, our study reveals that enterocyte specific Raptor is required for initiating a type 2 immune response which appears to function through the regulation of mTORC1 activity.

Trichomonas associated protection against Salmonella infection

Abstract Colonization resistance (CR), defined as the ability of intestinal microbiota and host defenses to protect against pathogens, is the first line defense against intestinal infection. In our studies of innate immune recognition of intestinal Salmonella, we discovered Naip5−/− and Rag1−/− mice harbor microbiota that protect mice against Salmonella infection, which is associated with intestinal colonization by Tritrichomonas muris (Tm). Tm is a protozoon commonly found in laboratory, pet shop and wild mice, which has no definitive disease association. Recent studies have demonstrated Tm and other intestinal parasites are sensed by tastant receptors expressed by specialized intestinal tuft cells, which enhances intestinal barrier by tuft cell and goblet cell hyperlasia. Helminths and protozoa have been associated with changes in the intestinal microbiota, suggesting that intestinal protozoa may produce biologically significant alterations in the composition of gut bacteria. We demonstrate that Tm colonization of mice is associated with decreased inflammation in the intestine during Salmonella infection of streptomycin pretreated mice. Tm colonization is also associated with increased resistance to Salmonella infection and CR. Finally, we demonstrate that Tm colonized mice have an altered gut microbiome, suggesting that Tm cultivates a protective microbiome that helps prevent Salmonella colonization and infection. Our studies indicate that intestinal protozoa may influence the complex environment within the gut to help limit Salmonella invasion of the gut ecosystem and Salmonella induced intestinal inflammation, and provide insight into novel strategies that may help prevent Salmonella infection and transmission.

The common mouse protozoaTritrichomonas murisalters mucosal T cell homeostasis and colitis susceptibility

The mammalian gastrointestinal tract hosts a diverse community of microbes including bacteria, fungi, protozoa, helminths, and viruses. Through coevolution, mammals and these microbes have developed a symbiosis that is sustained through the host's continuous sensing of microbial factors and the generation of a tolerant or pro-inflammatory response. While analyzing T cell-driven colitis in nonlittermate mouse strains, we serendipitously identified that a nongenetic transmissible factor dramatically increased disease susceptibility. We identified the protozoan Tritrichomonas muris as the disease-exacerbating element. Furthermore, experimental colonization with T. muris induced an elevated Th1 response in the cecum of naive wild-type mice and accelerated colitis in Rag1-/- mice after T cell transfer. Overall, we describe a novel cross-kingdom interaction within the murine gut that alters immune cell homeostasis and disease susceptibility. This example of unpredicted microbial priming of the immune response highlights the importance of studying trans-kingdom interactions and serves as a stark reminder of the importance of using littermate controls in all mouse research.

Microbiological survey of mice (Mus musculus) purchased from commercial pet shops in Kanagawa and Tokyo, Japan.

Information regarding the prevalence of infectious agents in mice in pet shops in Japan is scarce. This information is particularly useful for minimizing the risk of potential transmission of infections to laboratory mice. Therefore, we surveyed infectious agents in mice from pet shops in Kanagawa and Tokyo, Japan. The survey was conducted in 28 mice from 5 pet shops to screen for 47 items (17 viruses, 22 bacteria and fungi, 10 parasites) using culture tests, serology, PCR, and microscopy. The most common viral agent detected was murine norovirus (17 mice; 60.7%), followed by Theiler’s murine encephalomyelitis virus (13 mice; 46.4%), and mouse hepatitis virus (12 mice; 42.8%). The most common agent amongst the bacteria and fungi was Pasteurella pneumotropica (10 mice; 35.7%), followed by Helicobacter ganmani and Pneumocystis murina (8 mice; 28.5%, for both). Tritrichomonas muris was the most common parasite (19 mice; 67.8%), followed by Spironucleus muris (13 mice; 46.4%), Aspiculuris tetraptera, and Syphacia obvelata (8 mice each; 28.5%). Remarkably, a zoonotic agent, Hymenolepis nana, was found in 7 mice (25%). Given these results, we suggest that the workers in laboratory animal facilities should recognize again the potential risks of mice outside of the laboratory animal facilities as an infectious source, and avoid keeping mice as pets or as feed for carnivorous reptiles as much as possible for risk management.

Determination of internal transcribed spacer regions (ITS) in Trichomonas vaginalis isolates and differentiation among Trichomonas species

The nucleotide sequence of the 5.8S rRNA gene and the flanked internal transcribed spacer (ITS) regions of six Trichomonas vaginalis isolates with different metronidazole sensitivity and geographic origin were genotyped. A multiple sequence alignment was performed with different sequences of other isolates available at the GenBank/EMBL/DDBJ databases, which revealed 5 different sequence patterns. Although a stable mutation in position 66 of the ITS1 (C66T) was observed in 26% (9/34) of the T. vaginalis sequences analyzed, there was 99.7% ITS nucleotide sequence identity among isolates for this sequence. The nucleotide sequence variation among other species of the genus Trichomonas ranged from 3.4% to 9.1%. Surprisingly, the % identity between T. vaginalis and Pentatrichomonas hominis was ~83%. There was >40% divergence in the ITS sequence between T. vaginalis and Tritrichomonas spp., including Tritrichomonas augusta, Tritrichomonas muris, and Tritrichomonas nonconforma and with Tetratrichomonas prowazeki. Dendrograms grouped the trichomonadid sequences in robust clades according to their genera. The absence of nucleotide divergence in the hypervariable ITS regions between T. vaginalis isolates suggests the early divergence of the parasite. Importantly, these data show this ITS1-5.8S rRNA-ITS2 region suitable for inter-species differentiation.

Fingerprinting and Genetic Relationship of Trichomonas Vaginalis , Trichomonas Muris and Trichomonas Gallinae

Because of the common pathology, protein expression and drug resistance mechanisms-though in different hosts- of the luminal trichomonads Trichomonas vaginalis, T. gallinae and T. muris, doubts were raised concerning their phylogenetic relationship. The random amplified polymorohic (RAPD) technique for genetic DNA polymorphism studying was used to genetically characterize and assess their interspecies polymorphism. Results showed a high statistical support for the close relationship between the tested parasites and proved a tight association between Tritrichomonas muris and T. gallinae as well as a high genetic similarity between T. muris and T. vaginalis.

Fluorescence in situ hybridization for identification of Tritrichomonas foetus in formalin-fixed and paraffin-embedded histological specimens of intestinal trichomonosis

In the present study a highly species-specific oligonucleotide sequence of Tritrichomonas foetus 18S rRNA was used to design an antisense probe for identification of T. foetus in formalin-fixed and paraffin-embedded histological specimens by means of fluorescence in situ hybridization (FISH). Using archival histological specimens from several species with light microscopic evidence of intestinal trichomoniasis, and under optimized hybridization conditions, the probe positively identified trichomonads in colonic specimens from piglets and a kitten with PCR-confirmed T. foetus infection. Neither positive hybridization of the probe or PCR amplification of T. foetus DNA was observed in histological specimens from hamster (Tritrichomonas muris), turkey, nor mouse (Entamoeba muris) intestinal protozoal infections. Sequence-specific binding of the probe was further verified by successfully out-competing the hybridization with 10 x molar excess unlabeled probe and failure of a labeled sense probe to hybridize. The FISH assay described here enables simultaneous location and molecular identification of T. foetus in formalin-fixed and paraffin-embedded histological specimens of intestinal trichomoniasis. The methods employed are likely to also be applicable to probes designed for specific recognition of other trichomonad species, especially in mammalian tissue where red blood cell auto-fluorescence can be easily differentiated from the hybridization signal of trichomonads.

Effects of Tritrichomonas muris on the Mouse Intestine: A Proteomic Analysis

Although Tritrichomonas muris is a common parasite often detected in experimental animals including mice, its pathogenesis in host animals remains unclear. Proteomics can be used to specifically analyze biochemical host-parasite interaction and immune responses of the host to parasites. However, proteomics have not yet been applied to T. muris studies. Here, the effects of T. muris on the host were analyzed by proteomics. We found that 10 different proteins were expressed in T. muris-infected mice intestines compared with non-infected intestines. The identified proteins represented several functions mainly related to stress, immune response, metabolism and signal transduction. The results suggest that T. muris infection may affect processes that are acclimatizing to the environmental changes caused by the infection in the mouse intestine.

Sanitary profile in mice and rat colonies in laboratory animal houses in Minas Gerais: I - Endo and ectoparasites

The sanitary conditions of 13 animal houses in nine public institutions in Minas Gerais, and the presence of endo and ectoparasites of mice and rats colonies kept in these facilities were evaluated. Data about barriers to prevent the transmission of diseases and a program of sanitary monitoring were obtained through a questionnaire and local visit. Parasitological methods were performed for diagnosing mite, lice, helminthes, and protozoa parasites in 344 mice and 111 rats. Data have shown that the majority of the animal houses had neither proper physical environment nor protection barriers to prevent the transmission of infections. Parasitological results have shown that only one animal house (7.7%) had parasite free animals, whereas the others have presented infected animals and the prevalences of parasites in the mice colonies were: Myobia musculi (23.1%); Myocoptes musculinus (38.5%); Radfordia affinis (15.4%); Syphacia obvelata (92.3%); Aspiculuris tetraptera (23.1%); Hymenolepis nana (15.4%); Spironucleus muris (46.2%); Giardia muris (46.2%); Tritrichomonas muris (53.8%); Trichomonas minuta (61.5%); Hexamastix muris (7.7%); and Entamoeba muris (84.6%). As for the rat colonies, the prevalences were: Poliplax spinulosa (8.1%); Syphacia muris (46.2%); Trichosomoides crassicauda (28.6%); Spironucleus muris (85.7%); Tritrichomonas muris (85.7%); Trichomonas minuta (85.7%); Hexamastix muris (14.3%) and Entamoeba muris (85.7%).