HIV-1 diversity and compartmentalization in urine, semen, and blood

HIV-1 persists indefinitely in multiple cellular reservoirs despite antiretroviral therapy. We previously demonstrated HIV-1 compartmentalization in kidney and urine. Here, we further characterized viruses in urine and when available, compared them to those present in semen from HIV-1 positive participants with detectable plasma viremia to further understand the viral dynamics in the upper and lower genitourinary tract. Blood and urine samples were obtained from 19 HIV-1 positive participants. Simultaneous semen samples were obtained from 16 of the 19 participants. HIV-1 envelope (env) gene sequences were obtained by single-genome amplification (SGA) and neighbor-joining trees were constructed using the Kimura 2-parameter model. HIV-1 env gene sequences were amplified from blood in 19/19 (100%) participants, urine in 18/19 (95%) participants, and semen in 12/16 (75%). In individuals from which both urine and semen samples were obtained, differences in viral shedding between the 2 sources were observed, where HIV-1 env sequences could only be amplified from either urine or semen. Longitudinal phylogenetic analysis of urine-derived env sequences from 1 participant demonstrated that urine clusters distinct from blood are maintained over time (20 weeks), consistent with viral compartmentalization and local replication. Comparison of urine and semen derived sequences demonstrated either virus compartmentalization or equilibration. Our results demonstrate that when present, viral compartmentalization in urine persists over time. Comparison of timing of viral shedding in urine and semen samples from our cohort suggest different viral kinetics between the upper and lower genitourinary tract and sequence analysis suggests that HIV-1 populations in urine and semen can either be imported from blood or produced locally.