title: Evaluation of the immunogenicity and the protective efficacy of a novel identified immunogenic protein, SsPepO, of Streptococcus suis serotype 2.
abstract: Streptococcus suis serotype 2 (S. suis 2) is an important porcine and human pathogen. Some proteins secreted by S. suis 2 are thought to play important roles in the pathogenesis of this organism and in its induced immune response. SsPepO has been previously identified as a secretary immunogenic protein using immunoproteomic techniques. In this study, we confirmed that the sequence of this protein is highly conserved in S. suis 2 and compared it with its homologues in other pathogens. To test the protective efficacy of SsPepO in animal models, the recombinant SsPepO protein was used to immunize mice and pigs. The results demonstrated that it could elicit a strong humoral antibody response and confer significant protection against challenge with a lethal dose of S. suis 2 in mice and pig models. In addition, the antisera against rSsPepO could efficiently inhibit bacterial growth in a whole blood assay and conferred significant protection against S. suis 2 infection in passive immunization experiments. Our findings suggest that SsPepO plays an important role in the pathogenesis of S. suis 2 and would be a promising subunit vaccine candidate.
authors.affiliation: College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Jinquan
authors.initials: J
authors.lastname: Li
authors.forename: Jin
authors.initials: J
authors.lastname: Xia
authors.forename: Chen
authors.initials: C
authors.lastname: Tan
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Chengkun
authors.initials: C
authors.lastname: Zheng
authors.forename: Huanchun
authors.initials: H
authors.lastname: Chen
authors.forename: Weicheng
authors.initials: W
authors.lastname: Bei
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000627:therapeutic use; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D001770:Blood Bactericidal Activity; D004195:Disease Models, Animal; D005260:Female; D007116:Immunization, Passive; D051379:Mice; D008807:Mice, Inbred BALB C; D012376:Rodent Diseases / Q000276:immunology / Q000401:mortality / Q000517:prevention & control; D013290:Streptococcal Infections / Q000276:immunology / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D022541:Streptococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D017011:Streptococcus suis / Q000276:immunology*; D016019:Survival Analysis; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D022541:Streptococcal Vaccines