(a) A screening assay was carried out to evaluate the release of IFN-γ from TIL 2369 in an overnight co-culture with peptide-pulsed 293-A1 cells that were pulsed individually with the top 56 candidate HLA-A*0101-binding peptides identified from 2369 mel (Supplementary Table 2), with the exception of peptides 35, 39 and 44, which overlapped with peptides 20, 33 and 43, respectively, and were not tested (NT). Peptides 24-56 (Supplementary Table 2) stimulated the release of less than 100 pg/ml of IFN-γ from TIL 2369 and are not depicted in this graph. The autologous 2369 mel stimulated the release of 20,838 pg/ml of IFN-γ from TIL 2369 in this assay. (b,c) 293-A1 cells were pulsed with the indicated concentrations of peptides in an overnight co-culture with TIL 2098, and IFN-γ release measured. d. 293-A1 cells were transiently transfected with the indicated constructs and evaluated for their ability to stimulate IFN-γ release from TIL 2369 in an overnight co-culture.