Transcriptional and methylation outcomes of didehydro-Cortistatin A use in HIV-1 infected CD4+T cells

Ongoing viral transcription from the reservoir of long-lived CD4+ T cells containing integrated HIV-1 DNA presents a barrier to cure and associates with poorer health outcomes for people living with HIV, including chronic immune activation and inflammation. We previously reported that didehydro-Cortistatin A (dCA), an HIV-1 Tat inhibitor, blocks HIV-1 transcription. We sought to extend this work and examine the impact of dCA on host immune CD4+ T cell transcriptional and epigenetic states. Here, we performed a comprehensive analysis of genome-wide transcriptomic and DNA methylation profiles upon long-term dCA-treatment of primary human memory CD4+ T cells. dCA prompted specific transcriptional and DNA methylation changes in cell cycle, histone, interferon-response and T cell lineage transcription factor genes, through inhibition of both HIV-1 and Mediator kinases. These alterations establish a tolerogenic Treg/Th2 phenotype, reducing viral gene expression and mitigating inflammation in primary CD4+T cells during HIV-1 infection. Additionally, dCA suppresses expression of lineage-defining transcription factors for Th17 and Th1 cells, critical HIV-1 targets and reservoirs. dCA’s benefits thus extend beyond viral transcription inhibition, modulating immune cell landscape to limit HIV-1 acquisition and inflammatory environment linked to HIV-infection.