title: The FAI protein of group C streptococci targets B-cells and exhibits adjuvant activity.
abstract: We have demonstrated that the fibrinogen-albumin-IgG receptor of group C streptococci (FAI) targets B-cells in vivo. We exploited the targeting properties of FAI to improve the immune responses stimulated by soluble antigens administered by the mucosal route. Enhanced systemic and mucosal immune responses were observed in mice after intranasal immunization when ovalbumin was fused to FAI or truncated derivatives. The FAI fragment encompassing the IgG- and fibrinogen-binding regions was the minimal domain exhibiting optimal carrier/adjuvant properties. The obtained results suggest that the FAI protein represents a useful tool to improve the immunogenicity of vaccine antigens.
authors.affiliation: Vaccine Research Group, Department of Microbial Pathogenesis and Vaccine Research, Division of Microbiology, GBF-German Research Centre for Biotechnology, Mascheroder Weg 1, D-38124 Braunschweig, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Schulze
authors.forename: Oliver
authors.initials: O
authors.lastname: Goldmann
authors.forename: Antonia
authors.initials: A
authors.lastname: Toppel
authors.forename: Eva
authors.initials: E
authors.lastname: Medina
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Guzmán
mesh_terms: D000276:Adjuvants, Immunologic / Q000235:genetics; D000281:Administration, Intranasal; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D005340:Fibrinogen / Q000378:metabolism; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000097:blood / Q000378:metabolism; D051379:Mice; D010047:Ovalbumin / Q000235:genetics / Q000276:immunology; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013291:Streptococcus / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D001426:Bacterial Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D011993:Recombinant Fusion Proteins; D005340:Fibrinogen; D010047:Ovalbumin