Fig. 2

Structures of non-replicating mRNA vaccines entering clinical trials against viral diseases. The structures of non-replicating mRNA vaccines contain 5’Cap, 5’UTR, ORF region, 3’UTR, and Poly(A) tail. The main difference between the vaccine structures is the material encoded in the ORF regions. This article presents three kinds of mRNA vaccines: preventive mRNA vaccines, antibody-based mRNA vaccines, and mRNA as an immunomodulator. In preventive mRNA vaccine, vaccines against RNA viruses include human metapneumovirus (hMPV), influenza virus (IAV), rabies virus (RABV), SARS-COV-2, ZIKA virus (ZIKV), human Immunodeficiency Virus (HIV), human cytomegalovirus (HCMV) and human papilloma virus (HPV). mRNA vaccines encoding antibodies only contain CHIKV-IgG against CHIKV. mRNA vaccines encode cytokines as an immunomodulator, such as IL-12, which activates the immune response