Cognate Antigen Engagement Induces HIV-1 Expression In CD4+ T Cells From People On Long-Term ART

Despite antiretroviral therapy (ART), HIV-1 persists in latently-infected CD4+ T cells, preventing cure. Antigens drive the proliferation of infected cells, precluding latent reservoir decay. However, the relationship between antigen recognition and HIV-1 gene expression is poorly understood since most studies of latency reversal use agents that induce non-specific global T cell activation. Here, we isolated rare CD4+ T cells responding to cytomegalovirus (CMV) or HIV-1 Gag antigens from participants on long-term ART and assessed T cell activation and HIV-1 RNA expression upon co-culture with autologous dendritic cells (DCs) presenting cognate antigens. Physiological presentation of cognate antigens induced broad T cell activation (median 42-fold increase in CD154+CD69+ cells) and significantly increased HIV-1 transcription (median 4-fold), mostly through the induction of rare cells with higher viral expression. Thus, despite low proviral inducibility, physiologic antigen recognition can promote HIV-1 expression, potentially contributing to spontaneous reservoir activity on ART and viral rebound upon ART interruption. ### Competing Interest Statement Aspects of the intact proviral DNA assay (IPDA) are the subject of a patent application ('Compositions and methods Related to characterizing proviral reservoirs', PCT/US16/28822) filed by Johns Hopkins University, and RFS is one of the inventors on this application. The other authors have declared that no conflict of interest exists.