LOSS OF MUCOSAL CD4-LYMPHOCYTES IS AN EARLY FEATURE OF HIV-INFECTION

T cell subsets in the gut mucosa are distinct populations and their im balance in HIV has specific implications in infection. Alterations in T cell subsets in duodenal biopsies were investigated in 17 asymptomat ic HIV patients, 24 AIDS patients and 10 controls with non-ulcer dyspe psia. Immunohistochemistry and immunofluorescence using MoAbs to CD3, CD4, CD8, CD68, CD45RA, CD45RO and gp120 were performed on frozen sect ions. In the lamina propria, there was a significant depletion of CD4 cells at all stages of HIV, but the density of CD8 lamina propria cel ls was increased. Intraepithelial lymphocytes were decreased in AIDS p atients. There was a significant correlation between cellular density and mucosal CD3+ lymphocytes, and between mucosal CD3+ and CD8+ lympho cytes. Although mucosal CD4,CD45RO+ 'memory' cells were decreased, CD8 ,CD45RO+ 'memory' cells were increased. Mucosal CD4+ lymphocyte deplet ion occurred early in HIV, and thus their role in mucosal protection a gainst opportunistic infection should be revised. Mucosal CD8+ lymphoc ytes initially increased, but decreased when CD4 blood counts were dep leted, perhaps contributing to loss of host protection against infecti on. Intraepithelial lymphocyte depletion may also contribute to opport unistic infection.