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1,704 result(s) for "Trichomonas vaginalis"
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Membrane-shed vesicles from the parasite Trichomonas vaginalis: characterization and their association with cell interaction
Trichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogenital tract, where it remains extracellular and adheres to epithelial cells. Infections range from asymptomatic to highly inflammatory, depending on the host and the parasite strain. Despite the serious consequences associated with trichomoniasis disease, little is known about parasite or host factors involved in attachment of the parasite-to-host epithelial cells. Here, we report the identification of microvesicle-like structures (MVs) released by T. vaginalis . MVs are considered universal transport vehicles for intercellular communication as they can incorporate peptides, proteins, lipids, miRNA, and mRNA, all of which can be transferred to target cells through receptor–ligand interactions, fusion with the cell membrane, and delivery of a functional cargo to the cytoplasm of the target cell. In the present study, we demonstrated that T. vaginalis release MVs from the plasma and the flagellar membranes of the parasite. We performed proteomic profiling of these structures demonstrating that they possess physical characteristics similar to mammalian extracellular vesicles and might be selectively charged with specific protein content. In addition, we demonstrated that viable T. vaginalis parasites release large vesicles (LVs), membrane structures larger than 1 µm that are able to interact with other parasites and with the host cell. Finally, we show that both populations of vesicles present on the surface of T vaginalis are induced in the presence of host cells, consistent with a role in modulating cell interactions.
Trichomonas vaginalis homolog of macrophage migration inhibitory factor induces prostate cell growth, invasiveness, and inflammatory responses
The human-infective parasite Trichomonas vaginalis causes the most prevalent nonviral sexually transmitted infection worldwide. Infections in men may result in colonization of the prostate and are correlated with increased risk of aggressive prostate cancer. We have found that T. vaginalis secretes a protein, T. vaginalis macrophage migration inhibitory factor (TvMIF), that is 47% similar to human macrophage migration inhibitory factor (HuMIF), a proinflammatory cytokine. Because HuMIF is reported to be elevated in prostate cancer and inflammation plays an important role in the initiation and progression of cancers, we have explored a role for TvMIF in prostate cancer. Here, we show that TvMIF has tautomerase activity, inhibits macrophage migration, and is proinflammatory. We also demonstrate that TvMIF binds the human CD74 MIF receptor with high affinity, comparable to that of HuMIF, which triggers activation of ERK, Akt, and Bcl-2–associated death promoter phosphorylation at a physiologically relevant concentration (1 ng/mL, 80 pM). TvMIF increases the in vitro growth and invasion through Matrigel of benign and prostate cancer cells. Sera from patients infected with T. vaginalis are reactive to TvMIF, especially in males. The presence of anti-TvMIF antibodies indicates that TvMIF is released by the parasite and elicits host immune responses during infection. Together, these data indicate that chronic T. vaginalis infections may result in TvMIF-driven inflammation and cell proliferation, thus triggering pathways that contribute to the promotion and progression of prostate cancer.
Draft Genome Sequence of the Sexually Transmitted Pathogen Trichomonas vaginalis
We describe the genome sequence of the protist Trichomonas vaginalis, a sexually transmitted human pathogen. Repeats and transposable elements comprise about two-thirds of the ~160-megabase genome, reflecting a recent massive expansion of genetic material. This expansion, in conjunction with the shaping of metabolic pathways that likely transpired through lateral gene transfer from bacteria, and amplification of specific gene families implicated in pathogenesis and phagocytosis of host proteins may exemplify adaptations of the parasite during its transition to a urogenital environment. The genome sequence predicts previously unknown functions for the hydrogenosome, which support a common evolutionary origin of this unusual organelle with mitochondria.
Structural elucidation of recombinant Trichomonas vaginalis 20S proteasome bound to covalent inhibitors
The proteasome is a proteolytic enzyme complex essential for protein homeostasis in mammalian cells and protozoan parasites like Trichomonas vaginalis (Tv) , the cause of the most common, non-viral sexually transmitted disease. Tv and other protozoan 20S proteasomes have been validated as druggable targets for antimicrobials. However, low yields and purity of the native proteasome have hindered studies of the Tv 20S proteasome ( Tv 20S). We address this challenge by creating a recombinant protozoan proteasome by expressing all seven α and seven β subunits of Tv 20S alongside the Ump-1 chaperone in insect cells. The recombinant Tv 20S displays biochemical equivalence to its native counterpart, confirmed by various assays. Notably, the marizomib (MZB) inhibits all catalytic subunits of Tv 20S, while the peptide inhibitor carmaphycin-17 (CP-17) specifically targets β2 and β5. Cryo-electron microscopy (cryo-EM) unveils the structures of Tv 20S bound to MZB and CP-17 at 2.8 Å. These findings explain MZB’s low specificity for Tv 20S compared to the human proteasome and demonstrate CP-17’s higher specificity. Overall, these data provide a structure-based strategy for the development of specific Tv 20S inhibitors to treat trichomoniasis. Here the authors report the structure of the proteasome of Trichomonas vaginalis (Tv), a protozoan causing trichomoniasis. It shows how inhibitors target this enzyme and provides basis for developing specific proteasome inhibitors to treat trichomoniasis.
Recent Advances in Biology, Host and Microbe Interactions of the Human Sexually Transmitted Parasite Trichomonas vaginalis
Trichomoniasis is the most common non-viral sexually transmitted infection in humans, with over 200 million people affected each year. This disease is associated with pre-term birth, low birth weight, and premature membrane rupture. Its causal pathogen, Trichomonas vaginalis (TV), is a prevalent sexually transmitted protozoan parasite that infects the urogenital tract through cytoadherence. TV infection alters TV gene expression and induces host immune responses, while TV-secreted exosomes carry RNA and protein cargoes that mediate extracellular signaling. This review summarizes recent discoveries of molecules that interact with host receptors involved in cytoadherence. We also discuss human innate and adaptive immune responses to TV infection via a variety of inflammatory mediators. Recent research on concurrent or endosymbiont relationships of TV with other urogenital microbes and cancers, is also examined. These studies not only highlight the necessity of understanding host–microbe interactions in TV pathogenesis but also provide a crucial insight into potential therapeutic targets of nitroimidazole-resistant TV strains.
A Review of Evidence-Based Care of Symptomatic Trichomoniasis and Asymptomatic Trichomonas vaginalis Infections
Trichomonas vaginalis is the most prevalent nonviral sexually transmitted infection, affecting an estimated 3.7 million women and men in the United States. Health disparities are prominent in the epidemiology of this infection, which affects 11% of women aged ≥40 years and a disproportionately high percentage of black women. Particularly high prevalences have been identified among sexually transmitted disease (STD) clinic patients and incarcerated individuals. This article reviews and updates scientific evidence in key topic areas used for the development of the 2015 STD Treatment Guidelines published by the Centers for Disease Control and Prevention. Current evidence is presented regarding conditions associated with Trichomonas vaginalis infection, including human immunodeficiency virus (HIV) and pregnancy complications such as preterm birth. Nucleic acid amplification tests and point-of-care tests are newly available diagnostic methods that can be conducted on a variety of specimens, potentially allowing highly sensitive testing and screening of both women and men at risk for infection. Usually, trichomoniasis can be cured with single-dose therapy of an appropriate nitroimidazole antibiotic, but women who are also infected with HIV should receive therapy for 7 days. Antimicrobial resistance is an emerging concern.
Probiotics in addition to metronidazole for treatment Trichomonas vaginalis in the presence of BV: a randomized, placebo-controlled, double-blind study
The purpose was to evaluate whether probiotics can increase the effectiveness of antimicrobial therapy. Ninety women with Trichomonas vaginalis (TV) in the presence BV were included in the study of regimens for therapy combination with metronidazole and vaginal probiotics. For 7 days, the probiotics group patients received metronidazole at 500 mg twice a day and 1 capsule of probiotic Gynophilus® vaginally twice a day; the placebo group patients in addition to metronidazole received a placebo instead of a probiotic. For the next 7 days, patients in both groups in order restore normal microflora were given the probiotics vaginally. Before the treatment, on the 4th, 8th, and 15th day of therapy complaints, pH and redox potential of the vaginal fluid were recorded, TV detection culturally, microflora of the vagina with the qPCR-RT and microscopically. Adding probiotics to traditional therapy of TV in the presence of BV increased the likelihood of cure from TV (88.6 and 42.9% in the probiotic and placebo groups, respectively) and from BV (63.6 and 11.9%, respectively). We have found that the addition of probiotics to antimicrobial therapy causes the decrease in the inflammatory response and significant changes in the vagina’s physicochemical parameters (decreased of the pH values, increased of the redox potential) already on the fourth day of the therapy. The changes in the metronidazole’s antimicrobial action implementation when a probiotic is added are the reason of increasing the TV therapy’s effectiveness in the BV presence.
Performance of a single-use, rapid, point-of-care PCR device for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis: a cross-sectional study
Timely detection and treatment are important for the control of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis. The objective of this study was to measure the performance of the Visby Medical Sexual Health Test, a single-use, point-of-care PCR device. Women aged 14 years and older who presented consecutively to ten clinical sites across seven US states were enrolled for a cross-sectional, single-visit study. Patients who consented to participate, and who had not used any exclusionary products in the genital area in the previous 48 h, provided self-collected vaginal swabs for testing with the investigational device. Untrained operators received the specimens and ran the device using the guide provided. Specimens had to be run within 2 h of collection to be considered valid. For comparison, patient-infected status was derived by testing clinician-collected vaginal specimens with the Hologic Aptima Combo 2 Assay and Aptima Trichomonas vaginalis Assay, as well as the BD ProbeTec CT/GC Qx Amplified DNA Assay and BD ProbeTec Trichomonas vaginalis Qx Assay. If the results of those assays did not match, the BD MAX CT/GC/TV was used as a tiebreaker. The primary outcomes were the sensitivity and specificity of the investigational device for the detection of C trachomatis, N gonorrhoeae, and T vaginalis compared with patient-infected status. Between Feb 25, 2019, and Jan 6, 2020, 1585 participants aged between 14 years and 80 years (mean 34·8 [SD 14·2]) were enrolled. 1555 participants had tests run with the investigational device, of whom 1532 (98·5%) had a valid result on either the first or repeat test. Among the patients with evaluable results (including a determinate patient-infected status), the device had a sensitivity of 97·6% (95% CI 93·2–99·2) and specificity of 98·3% (97·5–98·9) for C trachomatis (n=1457), sensitivity of 97·4% (86·5–99·5) and specificity of 99·4% (98·9–99·7) for N gonorrhoeae (n=1468), and sensitivity of 99·2% (95·5–99·9) and specificity of 96·9% (95·8–97·7) for T vaginalis (n=1449). This innovative, rapid, easy-to-use, single-use, point-of-care device to detect C trachomatis, N gonorrhoeae, and T vaginalis infections showed excellent sensitivity and specificity, and could represent an important advance in the development of rapid diagnostics for sexually transmitted infections and other infectious diseases. Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases.
Trichomonas vaginalis extracellular vesicles are internalized by host cells using proteoglycans and caveolin-dependent endocytosis
Trichomonas vaginalis, a human-infective parasite, causes the most prevalent nonviral sexually transmitted infection worldwide. This pathogen secretes extracellular vesicles (EVs) that mediate its interaction with host cells. Here, we have developed assays to study the interface between parasite EVs and mammalian host cells and to quantify EV internalization by mammalian cells. We show that T. vaginalis EVs interact with glycosaminoglycans on the surface of host cells and specifically bind to heparan sulfate (HS) present on host cell surface proteoglycans. Moreover, competition assays using HS or removal of HS from the host cell surface strongly inhibit EV uptake, directly demonstrating that HS proteoglycans facilitate EV internalization. We identified an abundant protein on the surface of T. vaginalis EVs, 4-α-glucanotransferase (Tv4AGT), and show using isothermal titration calorimetry that this protein binds HS. Tv4AGT also competitively inhibits EV uptake, defining it as an EV ligand critical for EV internalization. Finally, we demonstrate that T. vaginalis EV uptake is dependent on host cell cholesterol and caveolin-1 and that internalization proceeds via clathrin-independent, lipid raft-mediated endocytosis. These studies reveal mechanisms used to drive host:pathogen interactions and further our understanding of how EVs are internalized by target cells to allow cross-talk between different cell types.
Trichomonas vaginalis Exosomes Deliver Cargo to Host Cells and Mediate Host∶Parasite Interactions
Trichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogential tract where it remains extracellular and adheres to epithelial cells. Infections range from asymptomatic to highly inflammatory, depending on the host and the parasite strain. Here, we use a combination of methodologies including cell fractionation, immunofluorescence and electron microscopy, RNA, proteomic and cytokine analyses and cell adherence assays to examine pathogenic properties of T. vaginalis. We have found that T.vaginalis produces and secretes microvesicles with physical and biochemical properties similar to mammalian exosomes. The parasite-derived exosomes are characterized by the presence of RNA and core, conserved exosomal proteins as well as parasite-specific proteins. We demonstrate that T. vaginalis exosomes fuse with and deliver their contents to host cells and modulate host cell immune responses. Moreover, exosomes from highly adherent parasite strains increase the adherence of poorly adherent parasites to vaginal and prostate epithelial cells. In contrast, exosomes from poorly adherent strains had no measurable effect on parasite adherence. Exosomes from parasite strains that preferentially bind prostate cells increased binding of parasites to these cells relative to vaginal cells. In addition to establishing that parasite exosomes act to modulate host∶parasite interactions, these studies are the first to reveal a potential role for exosomes in promoting parasite∶parasite communication and host cell colonization.