XK and influenza: An octavalent vaccine candidate combining four mRNA-LNPs encoding 4 HA and 4 NA antigens from A/H1N1, A/H3N2, B/Victoria, and B/Yamagata demonstrated strong immunogenicity against all four influenza strains in vaccinated mice and completely protected against lethal challenge from three different virus strains (A/H1N1, A/H3N2, B/Yamagata).