The study aims to better characterize intestinal tissue-resident memory T cells (TRM) in people living with HIV-1 receiving suppressive antiretroviral therapy (ART). TRM cells are key components of tissue immunity and may contribute to HIV-1 persistence within the intestinal mucosa, a major viral reservoir. The phenotypic, transcriptomic, and functional characteristics of intestinal CD4+ and CD8+ TRM cells, their susceptibility to HIV-1 infection, and their potential role as viral reservoirs will be investigated. Blood samples and additional colonic biopsies obtained during routine clinically indicated colonoscopy will be collected from HIV-1-infected participants and HIV-seronegative controls.