title: Protective immunity induced by 67 K outer membrane protein of phase I Coxiella burnetii in mice and guinea pigs.
abstract: A 67 K outer membrane protein (OMP) isolated from phase I Coxiella burnetii QiYi strain was purified with monoclonal antibodies (MoAb) coupled to CNBr-Sepharose 4B. Chemical analyses of the 67 K protein showed that it contained seventeen kinds of amino acids and no LPS. The immunogenicity and protectivity of the 67 K protein against C. burnetii was evaluated in mice and guinea pigs by in vitro lymphocyte proliferation assay, delayed-type skin test, antibody conversion rate, and immunization and challenge tests. Intraperitoneal injection of the 67 K protein resulted in antibody production against phase I and II whole cell antigens. The anti-67 K antibody conversion rate was found to be 100% in mice and guinea pigs as well. Lymphocytes were responses in vitro to specific antigen. In addition, delayed-type hypersensitivity appeared two weeks after immunization with the 67 K protein. Moreover, 100% of mice and guinea pigs inoculated with the 67 K protein were protected against a challenge with 10(3) ID50 virulent C. burnetii. In conclusion, these results demonstrate that the 67 K OMP elicits in vivo and in vitro both B cell-mediated and T cell-mediated immunity in mice and guinea pigs. Thus the 67 K protein is a candidate for an effective subunit vaccine against Q fever.
authors.affiliation: Department of Microbiology, Third Military Medical College, Sichuan Province, People's Republic of China.
authors.forename: Y X
authors.initials: YX
authors.lastname: Zhang
authors.forename: N
authors.initials: N
authors.lastname: Zhi
authors.forename: S R
authors.initials: SR
authors.lastname: Yu
authors.forename: Q J
authors.initials: QJ
authors.lastname: Li
authors.forename: G Q
authors.initials: GQ
authors.lastname: Yu
authors.forename: X
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology* / Q000302:isolation & purification; D001428:Bacterial Vaccines / Q000276:immunology*; D016997:Coxiella burnetii / Q000276:immunology*; D005260:Female; D006168:Guinea Pigs; D006968:Hypersensitivity, Delayed; D007109:Immunity; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011778:Q Fever / Q000276:immunology* / Q000517:prevention & control
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines