A look into the testis as a reservoir for HIV and ZIKV—A reproductive biologist’s perspective

Studies have shown that the mammalian testis serves as a reservoir for viruses including HIV and Zika virus (ZIKV). For instance, although viral levels in the serum of HIV-infected individuals receiving standard antiretroviral therapy (ART) are virtually undetectable, viral levels remain notably high in immune-privileged sites, such as the testes, in these patients. These findings also suggest that some viruses have the capability of evading the physiological barrier conferred by the blood-testis barrier (BTB) to access the adluminal compartment behind the BTB. There they utilize the immune-privileged status of the testis to avoid the reach of immune cells of the host immune system that would mount an unwanted attack for their eradication. This thus allows certain viruses to maintain a viral pool in the testis. In this chapter, we review some recent data in the literature from a reproductive biologist’s perspective. This information should appeal to clinicians who are interested in the interface of spermatogenesis and virology