Recognition of endogenously processed HA-1H by high- and intermediate-avidity HA-1H–specific T-cell clones. T-cell clones underlined in red were classified as high avidity and clones underlined in green as intermediate avidity based on the functional screening with exogenously loaded peptide (Figure 1A-C). Results of representative unique clones are depicted. (A) IFN-γ production by HA-1H–specific T-cell clones after stimulation with an EBV-LCL panel containing 4 HA-1H^pos/HLA*02:01^pos targets, 1 HA-1H^pos/HLA*02:01^neg target, and 1 HA-1H^neg/HLA*02:01^pos target (R:S ratio, 1:6). A representative example of 3 experiments is shown. (B) Cytotoxic activity of HA-1H–specific T-cell clones against the same EBV-LCL panel. Cytotoxicity was measured in a standard ⁵¹chromium-release assay at an E:T ratio of 10:1. Symbols represent median percentages of lysis of triplicates. (C) IFN-γ production by HA-1H–specific T-cell clones after stimulation with a panel of primary malignant samples, containing 2 HA-1H^pos /HLA*02:01^pos ALL samples, 3 HA-1H^pos/HLA*02:01^pos AML samples, 1 HA-1H^pos/HLA*02:01^neg AML sample, and 1 HA-1H^neg/HLA*02:01^pos AML sample (R:S ratio, 1:6). (D) Cytotoxic activity of HA-1H–specific T-cell clones against the same panel of primary malignant samples. Cytotoxicity was measured in a standard ⁵¹chromium-release assay (E:T ratio, 10:1). Symbols represent median percentages of lysis of triplicates.