title: Construction and immunogenicity of a ∆apxIC/ompP2 mutant of Actinobacillus pleuropneumoniae and Haemophilus parasuis.
abstract: The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1), encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1) was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 × 10(7) CFU and 3.5 × 10(5) CFU respectively). The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.
authors.affiliation: College of Veterinary Medicine and Institute of Preventive Veterinary Medicine, Sichuan Agricultural University. csanjie@gmail.com.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Liu
authors.forename: Yuheng
authors.initials: Y
authors.lastname: Gong
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Cao
authors.forename: Xintian
authors.initials: X
authors.lastname: Wen
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Huang
authors.forename: Qigui
authors.initials: Q
authors.lastname: Yan
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.forename: Sanjie
authors.initials: S
authors.lastname: Cao
mesh_terms: D000189:Actinobacillus Infections / Q000517:prevention & control / Q000662:veterinary; D016977:Actinobacillus pleuropneumoniae / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D001428:Bacterial Vaccines / Q000382:microbiology*; D006192:Haemophilus Infections / Q000517:prevention & control / Q000662:veterinary; D044137:Haemophilus parasuis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D051379:Mice; D009154:Mutation; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control; D014613:Vaccines, Attenuated; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated