PDCD1 and neoplasm: To reduce the TCR mismatch of two genes encoding endogenous T cell receptor (TCR) chains, TCR α (TRAC) and TCR β (TRBC) were deleted from T cells, the expression of a synthetic tumor specific TCR transgene NY-ESO-1 was enhanced, and the gene encoding programmed cell death protein 1 (PD-1) was removed.