Abstract
RNA-based genetic immunization represents an alternative novel strategy for antigen-specific cancer vaccines. In the present paper we investigate the use of synthetic messenger RNA in an experimental melanoma model. We show that gene gun-based immunization using synthetic RNA mediates gene expression in the epidermis and effectively induces antigen-specific cellular and humoral immunity in mice in vivo. Importantly, bombardment of the skin with RNA coding for the melanocytic self-antigen TRP2 linked to the immunogenic protein EGFP was associated with protection against experimentally induced B16 melanoma lung metastases and vitiligo-like fur depigmentation. Our results provide a scientific basis for clinical trials using synthetic mRNA encoding melanocytic antigens linked to immunogenic helper proteins for vaccination of patients with melanoma.