title: Identification of a surface protective antigen, CSP of Streptococcus equi ssp. zooepidemicus.
abstract: Streptococcus equi ssp. zooepidemicus (Streptococcus zooepidemicus, SEZ) is an important pathogen associated with opportunistic infections of a wide range of species, including horses, pigs and humans. The absence of suitable vaccine confounds the control of SEZ infection. Cell surface protein (CSP) has been identified as an immunogenic protein in the previous study but its protective efficacy is not clear. In the present study, the purified recombinant CSP could elicit a significant humoral antibody response and could confer significant protection against challenge with lethal dose of SEZ in mice model. CSP could adhere to the HEp-2 cells confirmed by flow cytometry and inhibit adherence of SEZ to HEp-2 cells in an adherence inhibition assay. In addition, real-time PCR demonstrated that CSP was induced in vivo following infection of mice with SEZ. Our findings suggest that CSP may play a potential role in the pathogenesis of SEZ and could be a target for the development of a novel subunit vaccine against SEZ infection.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, North Third Road, Guangzhou Higher Education Mega Center, Guangzhou, Guangdong 510006, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.forename: Zigong
authors.initials: Z
authors.lastname: Wei
authors.forename: Yaosheng
authors.initials: Y
authors.lastname: Chen
authors.forename: Pingping
authors.initials: P
authors.lastname: Xiao
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Lu
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D001422:Bacterial Adhesion / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000382:microbiology; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013290:Streptococcal Infections / Q000517:prevention & control; D022541:Streptococcal Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D018502:Streptococcus equi / Q000276:immunology*; D016019:Survival Analysis; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D008565:Membrane Proteins; D022541:Streptococcal Vaccines; D014614:Vaccines, Synthetic