Cryo‐Inactivated Cancer Cells Derived Magnetic Micromotors for Tumor Immunotherapy

Abstract Immunotherapy represents a highly promising modality in cancer treatment, with substantial advancements in therapeutic strategies. The primary challenge lies in enhancing the efficacy of immunotherapy approaches. Here, novel cryo‐inactivated cancer cells (CICC) derived magnetic micromotors (CICC@FeMnP) are reported for tumor synergistic immunotherapy. Through the magnetic control, the CICC@FeMnP micromotors can on‐demand target and accumulate at the tumor site. The FeMnP can induce ferroptosis and then trigger immunogenic cell death of tumor cells. The CICC containing the whole cancer antigen can conduct vaccination effects. Together with the Mn ²⁺ ‐mediated cGAS‐STING pathway to stimulate the immune response, substantial anti‐tumor immune effects can be achieved. Importantly, the CICC@FeMnP micromotors not only facilitate the establishment of a collaborative anti‐tumor immune network to enhance effective tumoricidal immunity but also induce long‐lasting immune memory effects. These results contribute to the inhibition of tumor progression, recurrence and lung metastasis, thereby prolonging the overall survival of tumor‐bearing mice. This work underscores the potential of an engineered biohybrid micromotor system as an alternative therapeutic approach in immunotherapy to enhance efficacy against tumors.