Telomerase activity in lymph nodes and bone marrow from HIV-infected patients. (A) Telomerase activity in extracts equivalent to 10⁵, 10⁴, and 10³ purified CD4⁺ and CD8⁺ T cells isolated from PB (CD4 and CD8) and lymph node tissue (LN, CD4 and CD8) shown for one representative HIV-infected individual. (B) Telomerase activity in CD4⁺ and CD8⁺ T cells isolated from PB and LN from four HIV-infected individuals, as analyzed by the original TRAP assay. (C) Telomerase activity in extracts equivalent to 10⁴, 10³, and 10² total bone marrow cells from two HIV-infected patients after AIDS diagnosis and two HIV⁻ controls. Total bone marrow cell samples contained approximately 40% to 45% CD3⁺ cells, 4% CD19⁺ cells, and 2% CD34⁺ cells. In bone marrow samples from the AIDS patients, the percentage of CD4⁺ cells was decreased (6.5% compared with 15% in HIV⁻ samples) and the percentage CD8⁺ cells was increased (30% compared with 18%).