Trichomonas vaginalis infection in symbiosis with Trichomonasvirus and Mycoplasma

Abstract

Trichomonas vaginalis is a protozoan with an extracellular obligatory parasitic lifestyle exclusively adapted to the human urogenital tract and responsible for nearly a quarter billion sexually transmitted infections worldwide each year. This review focuses on symbiotic Trichomonasvirus and mycoplasmas carried by the protozoan, their molecular features and their role in altering the human vaginal microbiome and the immunopathogenicity of the parasite. Improved diagnostics and larger clinical interventional studies are needed to confirm the causative role of protozoan symbionts in the variable clinical presentation of trichomoniasis and its morbid sequelae, including adverse reproductive outcome, susceptibility to viral infections and cancer.

Keywords: Candidatus Mycoplasma girerdii; Endosymbionts; Microbiome; Mycoplasma hominis; Trichomoniasis; dsRNA viruses.

Fig. 1.

Light microscopic images of T. vaginalis taken by phase invert microscopy. Left image depicts free-swimming parasites isolated from a vaginal swab and placed into culture medium. Right image depicts in vitro infection of human vaginal epithelial cells with T. vaginalis. The epithelial cells are grown in a monolayer. The parasites appear over the vaginal epithelial surface as single organisms or in swarms of many closely assembled bodies. Size bars in each image represent 15 microns.