PDCD1 and liver cancer: ,41 In our study, we found that CAR (B2) T cells could kill liver cancer cells by targeting inducible PD-L1 in the immunosuppressive TME (Figure 5D), whereas B2 VNAR did not show a significant benefit in improving the cytotoxicity of CAR (GPC3) T cells even though it functionally blocked the interaction of PD-1 with PD-L1 (Figure S4).