Torque Teno Virus in the vagina: potential influence on health and disease

Torque Teno Virus (TTV) is one of the most prevalent dna viruses identified in the vagina. while its presence under a variety of conditions is undisputed, whether this is of functional relevance remains unresolved. in this review we question the prevailing assumption that TTV is an endogenous commensal virus with no role in health or disease at that site. we present data from published studies, and extrapolate from relevant related investigations, to suggest that TTV is likely an active contributor to both vaginal well-being and pathological processes. the host immune response to TTV is reviewed and how various aspects of this interaction may impact immunity to pathogenic microorganisms. whether the presence of TTV inhibits or potentiates the pathogenic potential of other viruses, as well as the possible involved mechanisms, is presented. properties of vaginal epithelial cells are described and the potential influences of TTV on their activities are delineated. Known differences in the composition of the vaginal bacterial microbiota are described and how these changes are reflected by concomitant alterations in the TTV level. Lastly, how detection of TTV in the vagina of female partners of infertile couples may be relevant to indicators of potential causation is reviewed. The sum of our efforts will hopefully encourage further TTV-related investigations, especially in women, and provide an enhanced understanding of the role of this virus in clinically relevant processes.