PMEL and neoplasm: Figure 3(a) shows that if these tumor cells were pretreated with IFNγ, they were lysed by the TCR T cells. MC2 peptide-loaded HLA-A2 positive B cells (BSM) were lysed very efficiently, whereas gp100 peptide-loaded B cells were not recognized. Additionally, TCR T cells produced IFNγ but not TNFα in response to IFNγ pretreated EB81-MEL-2 cells, although T cells produced both IFNγ and TNFα in response to MC2 peptide-loaded cells (Figure 3(b)). No IFNγ was produced by MC2/A2 TCR T cells in response to MC2pos/A2neg tumor cells (Supplementary Figure  1(b)).