hTERT-siTCR–transduced CD8⁺ T cells display epitope-specific responsiveness. (A) Representative flow cytometry plots showing staining of hTERT-siTCR–transduced CD8⁺ T cells with HLA-A*24:02/hTERT_461-469 tetramer. HLA-A*24:02/HIV tetramer was used as a negative control. (B) ⁵¹Cr-release assays were conducted by using hTERT-siTCR–transduced CD8⁺ T cells with unpulsed or hTERT_461-469 peptide-loaded (1 μM) K562-A24, K562, HLA-A*24:02⁺, or HLA-A*24:02⁻ allogeneic B-LCLs at the indicated effector:target (E/T) ratios. (C) Effect of HLA class I and class II blockade on the cytotoxic activity of hTERT-siTCR–transduced CD8⁺ T cells against the cognate peptide-pulsed (1 μM) K562-A24 was determined by ⁵¹Cr-release assays at an E/T ratio of 5:1. (D) hTERT-siTCR–transduced CD8⁺ T cells were tested in ⁵¹Cr release assays against K562 (negative control) and K562-A24 cells pulsed with the indicated concentrations of hTERT_461-469 peptide at an E/T ratio of 5:1. Error bars represent SDs. (E) Representative flow cytometry plots showing staining of K3-1 with the HLA-A*24:02/hTERT_461-469 tetramer (upper) and the irrelevant HLA-A*24:02/HIV-1 Env_584-592 tetramer (negative control; bottom). (F) IFN-γ production by hTERT-siTCR–transduced CD8⁺ T cells was measured by using a format similar to that described for panel D. The parental K3-1 CTL clone was tested in parallel.