HLA-DRB1 and neoplasm: 4211-TCR-1-transduced PBL were activated by co-culture with the MCF-7 only when the DRB1*04:01 was introduced in the tumor cell line, while irrelevant HLA introduction resulted only in baseline secretion of IFN-γ by the TCR-engineered T cells (Fig. 3H and Suppl.