Figure 7.

Applications of hydrogels for local delivery of immunotherapy. A) Hydrogel properties, such as charge and surface topography, can influence immune responses including by converting tumor-associated macrophages from immunosuppressive (M2) to antitumor (M1) phenotypes. B) Hydrogels may be employed for delivery of antigens and adjuvants in the form of cancer vaccines that generate tumor-specific immune responses. C) Release of ICD-inducing agents (with or without ICI) from hydrogels delivered via intratumoral injection can result in release of tumor antigens that can potentiate tumor-specific immune responses. D) Hydrogels can be used to increase tumor immune cell infiltration by releasing chemoattractants. Inclusion of immune-modulating agents within the hydrogel may provide an immunologic niche for immune cell integration and immunomodulation within macroporous hydrogels. E) Nanoparticles loaded with antigens and immunomodulators may be released from hydrogels and shuttled to lymph nodes via dendritic cells. F) Hydrogels can also be used for autologous transfer of immune cells, such as CAR-T cells, providing protection during injection and potentially improving cell localization and viability compared to free injection of cells.