BRAF peptide vaccine facilitates therapy of murine BRAF-mutant melanoma

Approximately, 50% of human melanomas are driven by BRAF mutations, which produce tumors that are highly immunosuppressive and often resistant to vaccine therapy. We introduced lipid-coated calcium phosphate nanoparticles (LCP NPs) as a carrier to efficiently deliver a tumor-specific antigen, the BRAFV600E peptide, to drive dendritic cell (DC) maturation and antigen presentation in C57BL6 mice. The BRAF peptide vaccine elicited a robust, antigen-specific cytotoxic T cell response and potent tumor growth inhibition in a murine BRAF-mutant melanoma model. Advanced BRAF-specific immune response was illustrated by IFN-γ production assay and cytotoxic T lymphocyte (CTL) assay. Remodeling of immunosuppressive modules within the tumor microenvironment further facilitated CTL infiltration. Thus, using LCP NPs to deliver the BRAF peptide vaccine is a promising strategy for the BRAF-mutant melanoma therapy.