Increased Proliferation within T Lymphocyte Subsets of HIV-Infected Adolescents

Proliferation within T lymphocyte subsets of HIV-infected adolescents was quantified by detection of Ki-67, a nuclear antigen found in cells in late G1, S, or G2 phases of the cell cycle. Median percentages and absolute counts of Ki-67+ cells for all subsets tested (CD4 naive and memory, CD8 naive and memory) were significantly higher for HIV-infected adolescents compared to uninfected controls. CD8 naive cells of HIV-infected adolescents had the greatest increase in rate of proliferation and number of proliferating cells compared to uninfected controls. In HIV-infected adolescents, the percentage and absolute number of proliferating CD4 naive cells were considerably lower than corresponding values for the other subsets. CD4 percent correlated inversely with Ki-67 expression in CD4 memory, CD8 naive, and CD8 memory cells, while Ki-67 expression in CD4 and CD8 memory cells correlated directly with average CD38 molecules/CD8 cell and absolute number of CD8/CD38/HLA-DR cells, consistent with T cell activatio...