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 therapeuticpotentialin the past few years, but the clinical response rate of immunotherapyis less than 20%. Encountering the high heterogeneity of tumors, itwill be a general trend to apply combined therapy for cancer treatment.Photodynamic therapy (PDT) transiently kills tumor cells by producingreactive oxygen species (ROS), while residual tumor cells are proneto metastasis, leading to tumor recurrence. In combination with tumorimmunotherapy, it is hoped to awaken the host immune system and eradicate residual tumor cells. Herein, cancer cell membrane-coated nanoparticlesas a platform to combine PDT, TLR7 agonist, and tumor antigen forthe enhancement of tumor therapeutic efficacy are designed. The finalbiomimetic nanoparticles (CCMV/LTNPs) can specifically kill tumorcells through PDT, while strong host antitumor immune responses areelicited to eliminate residue tumor cells under the help of immuneadjuvant and tumor antigen from the cancer cell membrane. In summary,a photoimmunotherapy strategy is designed that synergistically enhancesthe tumor therapeutic effects by killing tumor cells through PDT andactivating host antitumor immune responses through the co-deliveryof adjuvant and tumor antigen, which may offer a promising strategyfor clinical immunotherapy in the future.