500 Quantification of the HIV reservoir in the gut-associated lymphoid tissue

Abstract

OBJECTIVES/GOALS: The major obstacle to an effective cure or remission for HIV infection is the integration of HIV into the genome of long-lived resting cells which constitute the so-called viral reservoir. With this study we want to elucidate the changes of the gut-associated HIV reservoir at different stages of viral suppression METHODS/STUDY POPULATION: Recent studies have shown that after long-term (>7 years) clinical suppression of peripheral HIV RNA, the circulating viral reservoir does not seem to decline further and, in fact may expand. The gastrointestinal associated lymphoid tissue (GALT) harbors by far the largest fraction of the latently infected cells, however not much is known about its changes over time.We thus quantified the HIV viral reservoir in the GALT by identifying HIV viral transcripts via 10X single-cell RNA sequencing at two GALT-sites in five PWH and compared the amount of HIV RNA found in the group of PWH with early (< 7years) vs late (> 7years) peripheral virological suppression (plasma HIV RNA <20copies/mL). RESULTS/ANTICIPATED RESULTS: Study participants had been diagnosed with HIV infection for a median (IQR) of 31 (32-34) years and had consistently undetectable peripheral blood HIV RNA for the previous 8 (4-15) years. In PWH with consistent viral suppression < 7yrs, 4 (2-6) HIV transcripts were identified in the ileum and 25 (13 – 38) in the colon. In PWH with consistent viral suppression > 7yrs, 0 (0-4) HIV transcripts were identified in the ileum and 7 (14-11) in the colon. Based on these preliminary results we plan to expand our cohort and confirm these results using Proviral DNA quantification. We anticipate that the viral decay in the GALT will follow a slower dynamic than what has been reported for the peripheral blood achieving a steady state after more than 7 years of peripheral viral suppression. DISCUSSION/SIGNIFICANCE: Despite the remarkable progress the survival and quality of life of PWH, after forty years from its first discovery, HIV infection remains uncurable. Considering its critical role, efforts are needed to better understand the dynamics of the GALT-associated HIV reservoir.