Influence of intranasal immunization with synthetic peptides corresponding to conserved epitopes of M protein on mucosal colonization by group A streptococci.
A major virulence factor of group A streptococci is M protein, a surface-exposed fibrillar molecule of which there exist more than 80 distinct serological types. Antigenic variability resides largely in the amino-terminal region of M protein, whereas the carboxy-terminal half of the molecule is highly conserved among different M serotypes. We sought to determine whether mucosal immunization with conserved epitopes of M protein influences the course of mucosal colonization by group A streptococci in a mouse model. Synthetic peptides corresponding to sequences in the conserved region of M protein were covalently linked to the mucosal adjuvant cholera toxin B subunit. Mice were immunized intranasally with the peptide-cholera toxin B subunit conjugate or with cholera toxin B subunit alone and then challenged intranasally with live streptococci. Pharyngeal colonization by streptococci was measured for up to 15 days postchallenge. Mice immunized with synthetic peptides showed a significant reduction in colonization compared with the control group. The data demonstrate that immunity evoked by conserved portions of M protein influences the outcome of group A streptococcal infection at the nasopharyngeal mucosa in a mouse model.
Bessen
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D
Rockefeller University, New York, New York 10021.
Fischetti
V A
VA
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D000941:Antigens / Q000276:immunology*; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D002352:Carrier Proteins; D000939:Epitopes; D007070:Immunoglobulin A / Q000276:immunology; D051379:Mice; D009092:Mucous Membrane / Q000276:immunology / Q000382:microbiology; D009842:Oligopeptides / Q000138:chemical synthesis / Q000276:immunology; D010614:Pharynx / Q000276:immunology / Q000382:microbiology; D013045:Species Specificity; D013290:Streptococcal Infections / Q000517:prevention & control*; D013297:Streptococcus pyogenes / Q000276:immunology* / Q000472:pathogenicity; D014611:Vaccination; D014614:Vaccines, Synthetic / Q000276:immunology*
D000907:Antibodies, Bacterial; D000941:Antigens; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D002352:Carrier Proteins; D000939:Epitopes; D007070:Immunoglobulin A; D009842:Oligopeptides; D014614:Vaccines, Synthetic; C014689:streptococcal M protein