Project summary The latent reservoir is the primary barrier to curing HIV, but little is known about the nature of this reservoir or the molecular mechanisms that regulate it. Increasing evidence suggests that the size and nature of this reservoir is impacted by drugs of abuse. Cannabinoid (CB) abuse, in particular, is prevalent amongst people with HIV (PWH), but the impact of CBs on the latent HIV reservoir has not been investigated. CBs are known to have immuno-modulatory and anti-inflammatory activities through activation of the CB2 receptor that is widely expressed in immune cells, including CD4 T cells. Our hypothesis is that CB exposure during HIV infection alters the size, location and transcriptomic phenotype of the latent HIV reservoir through CB2-dependent activation of the AP-1 transcription factor in CD4 T cells. Consistent with this hypothesis we have recently discovered that cannabinoids promote reactivation of HIV from latency in a T cell model. Defining the impact of CBs on the latent HIV reservoir will be critical to designing appropriate approaches to clear the reservoir from PWH who use CBs. To achieve this goal we propose to use cutting edge methods from the fields of single cell multi-omic analysis to characterize the effect of CBs on the latent HIV reservoir, and to test the functional role of CB-activated pathways in HIV latency. In the R61 phase, we will use a primary cell HIV latency model to define the impact of CB exposure on the transcriptome and epigenome of latently infected cells. Additionally, we will use a cutting-edge single cell HIV assay to quantify the size and location of the intact HIV reservoir in a cohort of CB-using PWH compared to non CB-using PWH. For the R33 phase, we will combine the results from these studies with a detailed single cell genomic analysis of identify CB-regulated transcripts in the PBMCs and CD4 T cells from the CB-using PWH cohort. By integrating these datasets we aim to identify CB-regulated pathways that regulate the size and subcellular location of the HIV reservoir. Overall these results will advance our understanding of how CBs interact with the latent HIV reservoir at the molecular level.

Project narrative A large fraction of people with HIV (PWH) also use cannabanoids (CBs), but the impact of CB exposure on the HIV reservoir in these individuals is unknown. CBs can modulate numerous cellular signal pathways that can impact HIV replication, and our hypothesis is that CB exposure alters gene expression and chromatin structure in CD4 T cells that are latently infected with HIV. The goal of this proposal is to define the impact of CBs on latently infected cells, and to correlate reservoir properties with CB-regulated transcriptional signatures.