Dysfunction of Tax-specific CD8+ T-cells and inefficient CD8+ cell-mediated HTLV-1 control in AC#287. (A) For antigen-specific T-cell proliferation, PBMCs from #313 and #287 were cultured for 13 days with or without Tax peptide in the presence or absence of 0.1 μg/ml LPS. The number indicates the percentage of tetramer+ cells in CD8+ T-cells. (B, C) PBMCs were stimulated with or without 10 μM Tax peptide for 6 hrs. The expression of CD69 (B) and CD107a (C) in Tax-specific CD8+ T-cells was analyzed by flow cytometry. (B) Bar indicates the percentage of CD69+ cells in Tax-specific CD8+ T-cells. (C) The number represents the percentage of CD107a+ cells in Tax-specific CD8+ T-cells. (D) Whole PBMCs and CD8-depleted fractions in ACs (#287 and #313) were cultured for 7 days and HTLV-1 p19 in the supernatants were measured by HTLV-1 p19 ELISA. P value was determined by the unpaired t test.