title: Development of a vaccine against Streptococcus agalactiae in fish based on truncated cell wall surface anchor proteins.
abstract: Streptococcus agalactiae is an important fish pathogen and a leading cause of major economic losses to the aquaculture industry worldwide. In the present study, the two truncated recombinant proteins of cell wall surface anchor family of S agalactiae, CWSAP465 and CWSAP1035, were expressed in Escherichia coli, and their immunogenicity and efficacy against the bacterium were evaluated in tilapia and turbot. The results showed that the prokaryotic expression of the two constructs, p32a-CWSAP465 and p32a-CWSAP1035, gave rise to a high yield of soluble proteins with good immunogenicity. The immunisation-challenge study revealed that tilapia and turbot immunised with recombinant truncated proteins produced high levels of antibodies with a peak at four weeks after immunisation and were protected from a challenge by a virulent S agalactiae at a dose of 1×109colony forming units/ml. The recombinant truncated proteins had higher efficacy than the whole-cell inactivated vaccine. Therefore, the study demonstrated that CWSAP465 and CWSAP1035 are two viable vaccine candidates against S agalactiae in fish.
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, Southwest University School of Life Sciences, Chongqing 400715, China.
authors.forename: H
authors.initials: H
authors.lastname: Liu
authors.affiliation: Shandong Binzhou Animal Science & Veterinary Medicine Academy, Shandong Lvdu Bio-technology Company Limited, Binzhou, Shandong 256600, China.
authors.forename: S
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Shandong Binzhou Animal Science & Veterinary Medicine Academy, Shandong Lvdu Bio-technology Company Limited, Binzhou, Shandong 256600, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Binzhou Marine Environmental Monitoring Station, Binzhou, Shandong 256600, China.
authors.forename: G
authors.initials: G
authors.lastname: Ren
authors.affiliation: Shandong Binzhou Animal Science & Veterinary Medicine Academy, Shandong Lvdu Bio-technology Company Limited, Binzhou, Shandong 256600, China.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.affiliation: Shandong Binzhou Animal Science & Veterinary Medicine Academy, Shandong Lvdu Bio-technology Company Limited, Binzhou, Shandong 256600, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, Southwest University School of Life Sciences, Chongqing 400715, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China.
authors.forename: W
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D005393:Fish Diseases / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D005412:Flatfishes; D008565:Membrane Proteins / Q000276:immunology*; D013290:Streptococcal Infections / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D022541:Streptococcal Vaccines / Q000276:immunology*; D013292:Streptococcus agalactiae / Q000276:immunology*; D017210:Tilapia
chemical_list: D000907:Antibodies, Bacterial; D008565:Membrane Proteins; D022541:Streptococcal Vaccines
keywords: Cell wall surface anchor family protein; Fish; Recombinant protein; Streptococcus agalactiae; Truncated