Copresentation of Tumor Antigens and Costimulatory Molecules via Biomimetic Nanoparticles for Effective Cancer Immunotherapy.

Nanoparticle (NP)-based cancer immunotherapy has been extensively explored. However, the efficacy of existing strategies is often limited by the lack of effective tumor-specific antigens or the inability to present costimulatory signal or both. Here, we report a novel approach to overcoming these limitations through surface coating with dendritic-tumor fusion cell membranes, which present whole repertories of tumor-associated antigens in the presence of costimulatory molecules. Because antigen-presenting and costimulatory molecules are displayed on their surface, these NPs can efficiently penetrate immune organs and activate T cells. We show that these NPs can be utilized to prevent tumor development and regress established tumors, including tumors in the brain. We demonstrate that encapsulation of immune adjuvants further improves their efficacy. Due to their significant efficacy, the whole tumor antigen-presenting costimulatory NPs have the potential to be translated into clinical applications for treatment of various cancers.