Intranasal immunization with multivalent group A streptococcal vaccines protects mice against intranasal challenge infections.

We have previously shown that a hexavalent group A streptococcal M protein-based vaccine evoked bactericidal antibodies after intramuscular injection. In the present study, we show that the hexavalent vaccine formulated with several different mucosal adjuvants and delivered intranasally induced serum and salivary antibodies that protected mice from intranasal challenge infections with virulent group A streptococci. The hexavalent vaccine was formulated with liposomes with or without monophosphorylated lipid A (MPL), cholera toxin B subunit with or without holotoxin, or proteosomes from Neisseria meningitidis outer membrane proteins complexed with lipopolysaccharide from Shigella flexneri.

Immunogenicity of a 26-valent group A streptococcal vaccine.

A multivalent vaccine containing amino-terminal M protein fragments from 26 different serotypes of group A streptococci was constructed by recombinant techniques. The vaccine consisted of four different recombinant proteins that were formulated with alum to contain 400 microg of protein per dose. Rabbits were immunized via the intramuscular route at 0, 4, and 16 weeks.