Cell‐Based Delivery Systems: Emerging Carriers for Immunotherapy

Immunotherapy is leading a paradigm shift in the treatment of various diseases, including tumors, auto‐immune diseases, and infectious diseases. However, the limited response rate and systemic side effects significantly impede the clinical applications of immunotherapy. As natural carriers for proteins and molecules, cells with low immunogenicity and toxicity have attracted considerable attention for biomedical applications and have achieved encouraging progress especially in immunotherapy. The convergence of multiple disciplines has equipped cell‐based delivery systems with control over their spatiotemporal distribution to enhance treatment efficacy and reduce side effects. Here, an overview of the fundamentals and design principles of cell‐based delivery systems followed by a perspective that includes the most recent advances of various cells as delivery carriers, with a special focus on the implications of cell‐based delivery systems for immunotherapy is offered. This review summarizes the recent advances in cell‐based delivery systems and their emerging applications with a focus on immunotherapy for cancers, infectious diseases, and auto‐immune diseases. Specifically, the designing principles, clinical limitations, and future directions of cell‐based delivery systems for immunotherapy are discussed, which will inspire interdisciplinary integration and collaboration to develop the next generation of bioinspired delivery systems.