Immune Modulation by Exosomes in Trichomonas Vaginalis Infection

Exosomes and their microRNA cargo have been shown to modulate immune gene expression in the context of cancer; however, they are still a largely uncharted territory in the context of reproductive tract immunology. We used a human in-vitro model of the most common non-viral infection of the lower female reproductive tract caused by the protozoan parasite Trichomonas vaginalis (TV) to begin unveiling the role of exosomes in the host-microbe interactions in this anatomic compartment. We isolated exosomes from monocultures of different TV strains and from vaginal epithelial-TV co-cultures and investigated their effects on the acute immune response by bystander upper reproductive tract endocervical epithelial cells and peripheral blood mononuclear leukocytes (PBMC). It has previously been shown that TV carries endosymbiotic dsRNA Trichomonas vaginalis virus (TVV), which amplifies inflammatory responses to TV via TLR3 signaling.^ Our experimental data showed that the immuno-inflammatory effects of exosomes derived from TVV-positive parasites differ from those derived from TVV-negative parasites, including TVV-cured isogenic strains, suggesting a new role of the virus in the host-parasite