title: Protective effect of a DNA vaccine containing an open reading frame with homology to an ABC-type transporter present in the genomic island 3 of Brucella abortus in BALB/c mice.
abstract: The immunogenicity of a DNA vaccine containing an open reading frame (ORF) of genomic island 3 (GI-3), specific for Brucella abortus and Brucella melitensis, has been examined. Intramuscular injection of plasmid DNA carrying the open reading frame with homology to an ABC-type transporter (pV278a) into BALB/c mice elicited both humoral and cellular immune responses. Mice injected with pV278a had a dominant immunoglobulin G2a (IgG2a) response. This DNA vaccine elicited a T-cell-proliferative response and induced significant levels of interferon gamma (INF-γ) upon restimulation with recombinant 278a protein. Upon stimulation with an appropriate recombinant protein or crude Brucella protein, the vaccine did not induce IL-4, suggesting a typical T-helper (TH1) response. Furthermore, the vaccine induced protection in BALB/c mice when challenged with the virulent strain Brucella abortus 2308. Taken together, these data suggest that DNA vaccination offers an improved delivery of the homologous of an ABC-type transporter antigen, and provides the first evidence of a protective effect of this antigen in the construction of vaccines against B. abortus.
authors.affiliation: Molecular Immunology Laboratory, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile.
authors.forename: Roberto
authors.initials: R
authors.lastname: Riquelme-Neira
authors.forename: Angello
authors.initials: A
authors.lastname: Retamal-Díaz
authors.forename: Francisca
authors.initials: F
authors.lastname: Acuña
authors.forename: Pablo
authors.initials: P
authors.lastname: Riquelme
authors.forename: Alejandra
authors.initials: A
authors.lastname: Rivera
authors.forename: Darwin
authors.initials: D
authors.lastname: Sáez
authors.forename: Angel
authors.initials: A
authors.lastname: Oñate
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000276:immunology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D002004:Brucella Vaccine / Q000235:genetics / Q000276:immunology*; D002003:Brucella abortus / Q000235:genetics; D017347:Brucella melitensis / Q000235:genetics; D002006:Brucellosis / Q000517:prevention & control*; D005260:Female; D044404:Genomic Islands; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D016366:Open Reading Frames; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*
chemical_list: D018528:ATP-Binding Cassette Transporters; D000907:Antibodies, Bacterial; D002004:Brucella Vaccine; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D007371:Interferon-gamma
keywords: ABC-type transporter; Brucella abortus; Brucellosis; DNA vaccine; Genomic island 3 (GI-3); Immune response; Protection