IL-21 和 CXCL9 工程化的 GPC3 特异性 CAR-T 细胞联合 PD-1 阻断增强抗肝细胞癌细胞毒活性

The application of CAR-T cells in solid tumors poses several challenges, including poor T cell homing ability, limited infiltration of T cells and an immunosuppressive tumor environment. In this study, we developed a novel approach to address these obstacles by designing GPC3-specific CAR-T cell that co-express IL-21 and CXCL9 (21 9 GPC3 CAR-T cells) and blocking the PD-1 expression on it.

The proliferation, cell phenotype, cytokine secretion and cell migration of indicated CAR-T cells were evaluated in vitro. The cytotoxic activities of genetically engineered CAR-T cells were accessed in vitro and in vivo. Compared to conventional GPC3 CAR-T cells, the 21 9 GPC3 CAR-T cells demonstrated superior proliferation, cytokine secretion and chemotaxis capabilities in vitro.

Furthermore, when combined with PD-1 blockade, the 21 9 GPC3 CAR-T cells exhibited enhanced proliferation, cytokine secretion and enrichment of effector T cells such as CTL, NKT and TEM cells. In xenograft tumor models, the PD-1 blocked 21 9 GPC3 CAR-T cells effectively suppressed HCC xenograft growth and increased T cell infiltration.

Overall, our study successfully generated GPC3 CAR-T cells expressing both IL-21 and CXCL9, demonstrated that combining PD-1 blockade can further enhance CAR-T cell function by promoting proliferation, cytokine secretion, chemotaxis and antitumor activity.

These findings present a hopeful and potentially effective strategy for GPC3-positive HCC patients.