Injectable and photocurable CAR-T cell formulation enhances the anti-tumor activity to melanoma in mice

The chimeric antigen receptor-T cells (CAR-T) therapy, as a novel personalized immunotherapy, has shown prominent clinical efficacy in the treatment of B-cell malignancies. However, the progress in solid tumors was hindered by multiple elements in the tumor immunosuppressive microenvironment. In this study, an injectable and photocurable Gelatin Methacryloyl (GelMA) hydrogel was applied to be a depot of CAR-T cells, thus forming an injectable CAR-T Gelatin Methacryloyl hydrogels Delivery (i-GMD) system. According to our results, CAR-T cells in this system could be normally amplified, sustained released, and play an anti-tumor role in vitro. When compared with local or intravenously injection of CAR-T solution, injection of i-GMD matrix around tumor demonstrated enhanced anti-tumor effect and markedly extended survival of mice. Our research outcomes indicated that this therapeutic strategy might hopefully provide a treatment for patients with unresectable tumors.