Reduced Metabolic Flux Protects a Rare Subset of HIV-Expressing CD4+ T-cells from CTL-mediated Elimination 2167

Abstract Description Cells expressing HIV antigens persist after years of antiretroviral therapy (ART) despite surveillance by HIV-specific cytotoxic T-lymphocytes (CTL) – indicating that some infected cells recognized by CTL may be resistant to elimination. We use a primary in vitro infection model and cells from people living with HIV (PLWH) to evaluate mechanisms of CTL resistance. CD4+ T-cells surviving co-culture with CTL after infection with either a WT HIV strain (survivors) or a variant containing a CTL escape mutation (bystanders) were evaluated by CITE-seq and metabolic profiling. Survivors exhibited markedly reduced expression of aerobic respiration gene-sets, total bioenergetic capacity and glucose metabolism compared to bystanders. This culminated in an enrichment of cells producing lower levels of ROS. Treatment of infected cells with a hypoxia-inducing, FDA-approved drug Deferoxamine (DFO) enhanced their susceptibilities to elimination by CTL. Analysis of CD4+ T-cells from PLWH sorted based on ROS accumulation revealed enrichment of total and intact HIV DNA in ROS-lo populations compared to ROS-hi and unenriched cells. We identify a quiescent metabolic program with low production of ROS as a protective feature of HIV-expressing cells to CTL attack. This program also enriches for integrated proviruses in PLWH. Treatment with DFO improves CTL-mediated elimination of HIV-expressing cells highlighting metabolic perturbation as a strategy to eliminate persistent HIV-infected cells. Funding Sources NIH REACH grants UM1AI164565 and R01AI170245. Topic Categories Vaccines and Immunotherapy (VAC)