title: Immunogenicity and protective efficacy of recombinant Haemophilus parasuis SH0165 putative outer membrane proteins.
abstract: Haemophilus parasuis (H. parasuis), the causative agent of swine polyserositis, polyarthritis, and meningitis, is one of the most important bacterial diseases of pigs worldwide. Little vaccines currently exist that have a significant effect on infections with all pathogenic serovars of H. parasuis. H. parasuis putative outer membrane proteins (OMPs) are potentially essential components of more effective vaccines. Recently, the genomic sequence of H. parasuis serovar 5 strain SH0165 was completed in our laboratory, which allow us to target OMPs for the development of recombinant vaccines. In this study, we focused on 10 putative OMPs and all the putative OMPs were cloned, expressed and purified as HIS fusion proteins. Primary screening for immunoprotective potential was performed in mice challenged with an LD50 challenge. Out of these 10 OMPs three fusion proteins rGAPDH, rOapA, and rHPS-0675 were found to be protective in a mouse model of H. parasuis infection. We further evaluated the immune responses and protective efficacy of rGAPDH, rOapA, and rHPS-0675 in pig models. All three proteins elicited humoral antibody responses and conferred different levels of protection against challenge with a lethal dose of H. parasuis SH0165 in pig models. In addition, the antisera against the three individual proteins and the synergistic protein efficiently inhibited bacterial growth in a whole blood assay. The data demonstrated that the three proteins showed high value individually and the combination of rGAPDH, rOapA, and rHPS-0675 offered the best protection. Our results indicate that rGAPDH, rOapA, and rHPS-0675 induced protection against H. parasuis SH0165 infection, which may facilitate the development of a multi-component vaccine.
authors.affiliation: Division of Animal Infectious Disease, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Shulin
authors.initials: S
authors.lastname: Fu
authors.forename: Minmin
authors.initials: M
authors.lastname: Zhang
authors.forename: Juan
authors.initials: J
authors.lastname: Xu
authors.forename: Jiwen
authors.initials: J
authors.lastname: Ou
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Huazhen
authors.initials: H
authors.lastname: Liu
authors.forename: Jinlin
authors.initials: J
authors.lastname: Liu
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 / Q000276:immunology; D000917:Antibody Formation / Q000276:immunology*; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D004195:Disease Models, Animal; D006192:Haemophilus Infections / Q000276:immunology* / Q000517:prevention & control*; D044137:Haemophilus parasuis / Q000235:genetics / Q000276:immunology*; D056724:Immunity, Humoral / Q000276:immunology; D051379:Mice; D011897:Random Allocation; D013552:Swine; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D014614:Vaccines, Synthetic