The programmable whole tumor cell vaccine with multiple immunogenicity enhancement strategies for high-efficiency antitumor immunotherapy

The therapeutic efficacy of whole tumor vaccine is limited by the relatively low immunogenicity, which determines subsequent activation of the immune response. In this study, we developed a whole tumor cell vaccine with multiple immunogenicity enhancement strategies, including CD47 knockout by CRISPR/Cas9 gene editing based on non-viral polymer gene carriers, membrane insertion of immune adjuvant DSPE-PEG-Mannose and heat-induced immunogenic cell death. Specifically, CD47 knockout blocks the CD47/SIRPα “don’t eat me” signal between tumor cells and APCs, thereby enhancing APC-mediated phagocytosis of tumor cells. Next, the adjuvant DSPE-PEG-Mannose onto the surface of CD47KO B16F10 cells using a simple membrane insertion method for stimulating the maturation of bone marrow-derived dendritic cells (BMDCs) and triggering a stronger immune response. Finally, heat treatment via a simple water bath induced immunogenic cell death (ICD), leading to cell inactivation while releasing specific damage-associated molecular patterns (DAMPs) to activate both the innate and adaptive immune systems. After the programmable process of CD47 gene editing, insertion of immune adjuvants and heat-induced death, the tumor cells transformed into a highly immunogenic whole tumor cell vaccine, achieving significant tumor prevention and therapeutic effects. This work provided a novel, simple, and effective strategy for the construction of a whole tumor cell vaccine.