Functional evaluation of dendritic cells and extracellular vesicles as immunotherapy for breast cancer.

Dendritic cells (DCs) play critical roles in recognizing and presenting antigens to T cells. They secrete dendritic cell-derived extracellular vesicles (DC-sEVs), which could mimic the function of DCs. Therefore, we explore the possibility of using DC-sEVs as a potential personalized vaccine in this study. We compared the efficacy of DCs and DC-sEVs on stimulating the immune system to target breast cancer cells and found that DC-sEVs had significantly more MHC molecules on the surface when compared to the parental DCs. In our in vivo and in vitro testing, Dc-sEVs showed significant advantages over DCs, regarding efficacy, safety, storage, and potential delivery advantages. DC-sEVs were able to suppress the growth of immune-cold breast tumors, while DCs failed to do so. These results indicate the strong potential utility of DC-sEVs as a personalized immunotherapy for breast cancer.