MLANA and melanoma: Moreover, A375 melanoma cells, which lack endogenous expression of both B*18:01 and MART1, became reactive to B*18:01/MART125-33 TCR-transduced T cells only when both the B*18:01 and full-length MART1 genes (but not either of the single genes) were transduced (Figure 5C, Figure 5—figure supplements 6A and 7B).