Characterization of HIV-1-specific cytotoxic T lymphocytes expressing the mucosal lymphocyte integrin CD103 in rectal and duodenal lymphoid tissue ofHIV-1-infected subjects

Acute HIV-1 infection depletes CD4(+) T cells in gut-associated lymphoid ti ssue (GALT). The failure of containment of local viral replication, and con sequent CD4(+) T cell depletion, might be due to delayed mobilization of ef fector CD8(+) T cells or absence of functioning HIV-1-specific CD8(+) T cel l effecters within GALT No studies have addressed human intestinal HIV-1-sp ecific CD8(+) T cell functions. We sought to determine whether functional H IV-1-specific CTL were present in GALT and whether the repertoire differed from HIV-1-specific CTL isolated from peripheral blood mononuclear cells. F rom three HIV-1-infected subjects, we isolated HIV-1-specific CD8(+) T cell s expressing the mucosal lymphocyte integrin CD103 from GALT. These antigen -specific effector cells could be expanded in vitro and lysed target cells in an MHC class t-restricted manner. HIV-1-specific CTL could be isolated f rom both duodenal and rectal GALT sites, indicating that CD8(+) effecters w ere widespread through GALT tissue. The breadth and antigenic specificities of GALT CTL appeared to differ from those in peripheral blood in some case s. In summary, we found HIV-1-specific CD8(+) effector T cells in GALT, des pite HIV-1-induced CD4(+) T cell lymphopenia. This suggests that HIV-1-spec ific CTL in gut tissue can be maintained with limited CD4(+) T cell help. ( C) 2000 Academic Press.