Multivalent streptococcal vaccine protects mice against infection.

2004 JUL 7 - (NewsRx.com & NewsRx.net) -- 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," scientists in the United States and Canada report.

"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," said Mary A. Hall and collaborators at the University of Tennessee and ID Biomedical Corporation of Washington in the U.S. and the ID Biomedical Corporation of Quebec in Canada. "Intranasal immunization with the hexavalent vaccine mixed with these adjuvants resulted in significant levels of antibodies in serum 2 weeks after the final dose."

"Mean serum antibody titers were equivalent in all groups of mice except those that were immunized with hexavalent protein plus liposomes without MPL, which were significantly lower," reported Hall and her colleagues. "Salivary antibodies were also detected in mice that received the vaccine formulated with the four strongest adjuvants. T-cell proliferative assays and cytokine assays using ...