PDCD1 and neoplasm: To edit the PDCD1 locus of tumor-specific TCR-T cells that recognize the cancer testis antigen, NY-ESO-1157–165 SLLMWITQV (NY-ESO-1 TCR-T cells) (39), we first transduced T cells with lentivirus encoding NY-ESO-1 TCR and then subsequently conducted Cas9 RNP/AAV6 knock-in into transduced T cells (Figure 1B).