Towards efficient cancer immunotherapy: advances in developing artificial antigen-presenting cells.

Active anti-cancer immune responses depend on efficient presentation of tumor antigens and co-stimulatory signals by antigen-presenting cells (APCs). Therapy with autologous natural APCs is costly and time-consuming and results in variable outcomes in clinical trials. Therefore, development of artificial APCs (aAPCs) has attracted significant interest as an alternative. We discuss the characteristics of various types of acellular aAPCs, and their clinical potential in cancer immunotherapy. The size, shape, and ligand mobility of aAPCs and their presentation of different immunological signals can all have significant effects on cytotoxic T cell activation. Novel optimized aAPCs, combining carefully tuned properties, may lead to efficient immunomodulation and improved clinical responses in cancer immunotherapy.