Mycoplasma hominis and Trichomonas vaginalis symbiosis: multiplicity of infection and transmissibility of M-hominis to human cells

We recently reported that most Trichomonas vaginalis isolates cultured in v itro are infected by Mycoplasma hominis. In this work, we have characterize d some aspects of the relationships between the two microorganisms. PCR, cu ltivation, and immunological methods revealed that the number of M. hominis organisms carried by T. vaginalis in culture varied from isolate to isolat e, suggesting a specific multiplicity of infection. Moreover, infected T. v aginalis isolates were able to pass bacteria not only to M. hominis-free pr otozoa, but also to human-derived epithelial cells. The in vitro transmissi on of the bacterium from T. vaginalis to both uninfected parasite isolates and human epithelial cells suggests a role for T. vaginalis as a carrier of the M. hominis infection in vivo.