Correlation between telomere length/telomerase activity of HIV-1–specific CD8⁺ T cells and their proliferative and cytotoxic activity. (A) Representative dot plots indicating gating of proliferating (CFSE^dim) and nonproliferating (CFSE^bright) tetramer⁺ HIV-1–specific CD8⁺ T cells. Numbers in quadrants reflect proportion of tetramer⁺ CD8⁺ T cells. (B) Comparison of telomere lengths between proliferating and corresponding nonproliferating tetramer⁺ HIV-1–specific CD8⁺ T cells. Horizontal bars reflect medians. (C) Representative dot plots reflecting caspase-3 expression in peptide-pulsed target cells following exposure to HIV-1–specific CD8⁺ T cells from individuals with progressive or controlled viremia. Numbers in quadrants reflect proportion of target cells. (D) Proportion of caspase-3–positive target cells after coincubation with PBMCs from HIV-1 controllers (n = 5) or HIV-1 progressors (n = 5). Horizontal bars reflect means. (E) Correlation between cytotoxic activity of HIV-1–specific CD8⁺ T cells (measured by proportion of caspase-3–positive target cells) and corresponding telomere length.