The immmunochemical analysis (Figure 7E) showed that there were more T cells infiltration in the tumor tissues treated by PD-1-deficient GPC3-CAR T cells compared with those treated by wild-type GPC3-CAR T cells, indicating that the disruption of PD-1 enhanced the infiltration of GPC3-CAR T cells in tumor tissues. Here, PDCD1 is linked to neoplasm.