Delayed Differentiation of Potent Effector CD8 T Cells Reducing Viremia and Reservoir Seeding in Acute HIV Infection

摘要

CD8⁺ T cells play a critical role in controlling HIV viremia and could be important in reducing HIV-infected cells in approaches to eradicate HIV. The SIV model provided the proof of concept for a CD8⁺ T cell-mediated reservoir clearance but showed conflicting evidences on the role of these cells to eliminate HIV-infected cells. In humans, HIV-specific CD8⁺ T cell responses have not been associated with a reduction of the HIV-infected cell pool in vivo. Here we studied HIV-specific CD8⁺ T cells in the RV254 cohort of individuals initiating ART in the earliest stages of acute HIV infection (AHI). We showed that the HIV-specific CD8⁺ T cells generated as early as AHI stage 1 and 2 prior to peak viremia are delayed in expanding and acquiring effector functions but are endowed with higher memory potential. In contrast, the fully differentiated HIV-specific CD8⁺ T cells at peak viremia in AHI stage 3 were more prone to apoptosis but were associated with a steeper viral load decrease after ART initiation. Importantly, their capacity to persist in vivo after ART initiation correlated with a lower HIV DNA reservoir. These findings demonstrate that HIV-specific CD8⁺ T cell magnitude and differentiation are delayed in the earliest stages of infection. These results also demonstrate that potent HIV-specific CD8⁺ T cells contribute to reducing the pool of HIV-producing cells and the HIV reservoir seeding in vivo and provide the rationale to design of interventions aiming at inducing these potent responses to cure HIV infection.