Search

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. [ABSTRACT FROM AUTHOR]

To investigate the therapeutic effect of dendritic cells pulsed with lysates of heat-treated CT26 colon carcinoma cells. Bone marrow-derived DCs were pulsed with lysates of heat-treated tumor cells and were used to immunize BALB/c mice with established colon carcinoma. Cytotoxic T lymphocyte (CTL) response was detected. The therapeutic effect induced by DCs was observed by tumor weight and survival time. DCs pulsed with lysates of heat-treated tumor cells markedly induced specific cytotoxic activity of CTLs. Tumor growth in the immunized BALB/c mice was significantly inhibited and the survival time of the tumor-bearing mice was prolonged. DCs pulsed with lysates of heat-treated tumor cells have an observable therapeutic effect on established colon carcinoma-bearing mice. [ABSTRACT FROM AUTHOR]