Cancer Cell Membrane-Coated Nanoparticle Co-loaded with Photosensitizer and Toll-like Receptor 7 Agonist for the Enhancement of Combined Tumor Immunotherapy.

Tumor immunotherapy has shown considerable therapeutic potential in the past few years, but the clinical response rate of immunotherapy is less than 20%. Encountering the high heterogeneity of tumors, it will be a general trend to apply combined therapy for cancer treatment. Photodynamic therapy (PDT) transiently kills tumor cells by producing reactive oxygen species (ROS), while residual tumor cells are prone to metastasis, leading to tumor recurrence. In combination with tumor immunotherapy, it is hoped to awaken the host immune system and eradicate residual tumor cells. Herein, cancer cell membrane-coated nanoparticles as a platform to combine PDT, TLR7 agonist, and tumor antigen for the enhancement of tumor therapeutic efficacy are designed. The final biomimetic nanoparticles (CCMV/LTNPs) can specifically kill tumor cells through PDT, while strong host antitumor immune responses are elicited to eliminate residue tumor cells under the help of immune adjuvant and tumor antigen from the cancer cell membrane. In summary, a photoimmunotherapy strategy is designed that synergistically enhances the tumor therapeutic effects by killing tumor cells through PDT and activating host antitumor immune responses through the co-delivery of adjuvant and tumor antigen, which may offer a promising strategy for clinical immunotherapy in the future.