Emerging approaches for T cell-stimulating platform development.

T cells are key mediators of the adaptive immune response, playing both direct and supporting roles in the destruction of foreign pathogenic threats as well as pathologically transformed host cells. The natural process through which T cells are activated requires coordinated molecular interactions between antigen-presenting cells and T cells. Promising advances in biomaterial design have catalyzed the development of artificial platforms that mimic the natural process of T cell stimulation, both to bolster the performance of cell therapies by activating T cells ex vivo prior to adoptive cell transfer and to directly activate T cells in vivo as off-the-shelf treatments. This review focuses on innovative strategies in T cell-stimulating platform design for applications in cancer therapy. We specifically highlight progress in bead-based artificial antigen-presenting cell engineering, hydrogel-based scaffolds, DNA-based systems, alternative polymeric strategies, and soluble activation approaches. Collectively, these advances are expanding the repertoire of tools for targeted immune activation.