title: Mucosal and systemic immune responses to a recombinant protein expressed on the surface of the oral commensal bacterium Streptococcus gordonii after oral colonization.
abstract: To circumvent the need to engineer pathogenic microorganisms as live vaccine-delivery vehicles, a system was developed which allowed for the stable expression of a wide range of protein antigens on the surface of Gram-positive commensal bacteria. The human oral commensal Streptococcus gordonii was engineered to surface express a 204-amino acid allergen from hornet venom (Ag5.2) as a fusion with the anchor region of the M6 protein of Streptococcus pyogenes. The immunogenicity of the M6-Ag5.2 fusion protein was assessed in mice inoculated orally and intranasally with a single dose of recombinant bacteria, resulting in the colonization of the oral/pharyngeal mucosa for 10-11 weeks. A significant increase of Ag5.2-specific IgA with relation to the total IgA was detected in saliva and lung lavages when compared with mice colonized with wild-type S. gordonii. A systemic IgG response to Ag5.2 was also induced after oral colonization. Thus, recombinant Gram-positive commensal bacteria may be a safe and effective way of inducing a local and systemic immune response.
authors.affiliation: Laboratory of Bacterial Pathogenesis and Immunology, Rockefeller University, New York, NY 10021, USA.
authors.forename: D
authors.initials: D
authors.lastname: Medaglini
authors.forename: G
authors.initials: G
authors.lastname: Pozzi
authors.forename: T P
authors.initials: TP
authors.lastname: King
authors.forename: V A
authors.initials: VA
authors.lastname: Fischetti
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D000942:Antigens, Bacterial; D001180:Arthropod Venoms / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D002352:Carrier Proteins; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D009061:Mouth Mucosa / Q000382:microbiology; D009092:Mucous Membrane / Q000276:immunology*; D010614:Pharynx / Q000382:microbiology; D011993:Recombinant Fusion Proteins / Q000276:immunology; D013284:Stomatognathic System / Q000382:microbiology*; D013291:Streptococcus / Q000254:growth & development / Q000276:immunology*; D014863:Wasps
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001180:Arthropod Venoms; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D011993:Recombinant Fusion Proteins; C014689:streptococcal M protein