An Engineered Cytokine‐Induced Killer Cell‐Derived Nanovesicle Featuring Multiplexed Immune Activation Performances for Enhanced Tumor Therapy

ABSTRACT In this study, a multiplexed immune activation strategy is elaborately developed based on engineered cytokine‐induced killer (CIK) cell‐nanovesicles (DOX@CpG‐PNVs) with high tumor targeting, tumor killing and immunostimulatory functions for enhanced antitumor therapy. CIK‐derived cellular nanovesicles enriched with outer‐membrane molecules (e.g., FasL, TRAIL, and tumor chemokine receptors) are genetically engineered with the expression of programmed death‐1 (PD‐1), and further loaded with doxorubicin (DOX) and CpG ODN adjuvant to obtain DOX@CpG‐PNVs. Specifically, this unique designed nanovesicle harnesses the dual therapeutic characteristics: i) multiple immune activation, including PD‐1/PD‐L1 blockade to rescue cytotoxic T lymphocyte function, CpG‐mediated non‐MHC‐restricted immunostimulation, and DOX‐induced immunogenic cell death; ii) direct tumor cell killing triggered by DOX and apoptosis‐inducing ligands of FasL/TRAIL. Having killed tumor cells via multiple ways, DOX@CpG‐PNVs exhibited significant anti‐tumor effect, as evidenced on both immunogenic and poorly immunogenic tumors. Even in a poorly immunogenic tumor model, DOX@CpG‐PNVs achieves a tumor suppression rate of 75%. Such a synergistic approach cooperatively compensates for the defects of a single‐mode immunotherapy and overcomes the immunosuppressive milieu, offering a feasible bioactive material‐based strategy for treating various types of tumors.