Characterization of a MAGE-A2-_157-166-specific T cell. (A) FACS analysis of a MAGE-A2-_157-166-specific T-cell clone generated from patient 22 following staining with HLA-peptide tetramer HLA-A2/MAGE-A2-_157-166. Staining with tetramer is represented on the x-axis, and CD8⁺ staining is shown on the y-axis. (B) IFN-γ production by MAGE-A2-_157-166-specific T-cell clone following stimulation with peptide-loaded target cells (effector-target [E/T] ratio = 0.1:1). T2 target cells were loaded with peptide MAGE-A2-_157-166 and incubated with clone 1 from patient 22. IFN-γ production was observed following incubation with peptide-loaded targets (▪) but not unloaded targets (▦). (C) FACS analysis of a MAGE-A2_157-166-specific T-cell clone generated from patient 11 following staining with HLA-peptide tetramer HLA-A2/MAGE-A2-_157-166. Staining with tetramer is represented on the x-axis, and CD8⁺ staining is shown on the y-axis.