A multi-antigen mRNA vaccine for Listeria monocytogenes infection

A multi-antigen mRNA lipid nanoparticle vaccine targeting peptides presented on MHCI could help protect against Listeria monocytogenes infection. An immunopeptidomics screen of L. monocytogenes antigens in two infected human epithelial cell lines identified 68 MHCI-presented peptide antigens from 42 bacterial proteins; seven of those proteins, which contained antigens that were highly presented on both cell lines, were then encoded in nucleoside-modified mRNA and delivered in liposomes, in combination with an α-galactosylceramide adjuvant.

In mouse models of L. monocytogenes infection, vaccination with the L. monocytogenes mRNA vaccine on day zero and boosting on day 14 before infection on day 28 decreased bacterial colony forming units (CFU)s by 3 log in the spleen and 1.5 log in the liver compared with an mRNA vaccine encoding an irrelevant antigen. ...