title: Nasal immunization with recombinant Brucella melitensis bp26 and trigger factor with cholera toxin reduces B. melitensis colonization.
abstract: bp26 and trigger factor (Tf) DNA vaccines have previously been shown to protect against Brucella infection. In this study, purified bp26 and Tf proteins were tested in BALB/c mice for immunity and protection. The results showed that intranasal (i.n.) immunization with bp26 and Tf in conjunction with cholera toxin (CT) adjuvant elicit both elevated mucosal and systemic immune responses. While nasal immunization with either bp26 or Tf elicited elevated antibody responses, co-immunization with both enhanced anti-Tf immunity, suggesting bp26 adjuvant activity. Evaluation of serum IgG subclass responses showed elevated IgG1 titers. Further analysis to discern the source of immune B cells revealed effective immunization of respiratory tissues. However, Tf stimulated a significantly higher level of cytokine-forming cells (CFC) than bp26. These results imply that co-immunization of bp26 and Tf proteins elicits synergistic cooperation to stimulate the immune system. When immunized mice were challenged with B. melitensis 16M, bp26-plus Tf-immunized mice showed no difference in splenic weights but harbored three-fold less bacterial CFU when compared to sPBS-immunized control mice.
authors.affiliation: Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717-3610, USA.
authors.forename: Xinghong
authors.initials: X
authors.lastname: Yang
authors.forename: Nancy
authors.initials: N
authors.lastname: Walters
authors.forename: Amanda
authors.initials: A
authors.lastname: Robison
authors.forename: Theresa
authors.initials: T
authors.lastname: Trunkle
authors.forename: David W
authors.initials: DW
authors.lastname: Pascual
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000276:immunology*; D002004:Brucella Vaccine / Q000008:administration & dosage / Q000276:immunology*; D017347:Brucella melitensis / Q000187:drug effects / Q000254:growth & development / Q000276:immunology*; D002006:Brucellosis / Q000097:blood / Q000276:immunology / Q000517:prevention & control; D002772:Cholera Toxin / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D018928:Immunity, Mucosal / Q000276:immunology; D007114:Immunization / Q000379:methods*; D007074:Immunoglobulin G / Q000097:blood; D008214:Lymphocytes / Q000276:immunology; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000276:immunology / Q000382:microbiology
chemical_list: D000907:Antibodies, Bacterial; C106040:BP26 protein, Brucella; D001426:Bacterial Proteins; D002004:Brucella Vaccine; D007074:Immunoglobulin G; D008565:Membrane Proteins; D002772:Cholera Toxin