Ferritin nanoparticle-based SpyTag/SpyCatcher-enabled click vaccine for tumor immunotherapy.

Recently, tumor neoantigens have been attractive for development of personal therapeutic vaccines. However, how to instantly deliver multiple neoantigens for efficient anti-tumor immunity is still challenging. Here, we established a SpyCatcher-modified ferritin nanoparticle platform, which permits convenient and stable covalent conjugation with tumor specific antigens containing SpyTag in a click-link manner. These ferritin nanoparticles are rapidly drained to lymph nodes and target dendritic cells, especially CD8α+ population, upon subcutaneous immunization. Ferritin nanoparticles carrying HPV16 oncogene E7 peptide antigen or MC38 tumor derived mutant neoantigens elicit about 2-3 folds enhanced antigen-specific cytotoxic T lymphocyte (CTL) response than soluble peptide antigens and significantly suppress the growth of E7-related or MC38 tumors. The anti-tumor effect was further enhanced in combination with PD-1 checkpoint blockade. Together, our study provides a ferritin nanoparticle-based, SpyTag/SpyCatcher-enabled click vaccine platform, especially for personalized tumor immunotherapy.