title: DNA vaccine encoding molecular chaperone GroEL of Edwardsiella tarda confers protective efficacy against edwardsiellosis.
abstract: In the present study, molecular chaperone GroEL of Edwardsiella tarda was found both react with flounder (Paralichthys olivaceus) anti-recombinant GroEL (rGroEL) and anti-E. tarda antibodies, and it was both detected in the outer membrane and the secretome. To evaluate the vaccine potential of GroEL, pCI-neo-GFP-GroEL (pCG-GroEL) was prepared and used to vaccinate healthy flounder, and immune protective effects were investigated. The results showed that pCG-GroEL produced an RPS of 60% following E. tarda challenge at week 5 after immunization. Moreover, GroEL transcripts and GFP-tagged GroEL could be detected in vaccinated flounder after immunization with pCG-GroEL, and the GFP-tagged GroEL could be also detected in HINAE cells after transfection with pCG-GroEL. Meanwhile, the immune response of flounder induced by pCG-GroEL was investigated, and the results showed that: (1) the levels of specific serum antibodies against E. tarda induced by pCG-GroEL were significantly higher than other groups at 3-5 week post vaccination; (2) pCG-GroEL could induce the proliferation of sIg+ lymphocytes, and the levels of sIg+ lymphocytes in blood, spleen and pronephros of pCG-GroEL vaccinated fish were significantly increased compared with the PBS vaccinated fish at 3w, 2w and 2w after immunization, respectively; (3) MHCIα, MHCIIα, CD4-1, CD8α, IL-1β and TNF-α were significantly induced by immunization with pCG-GroEL, and the mRNA levels of CD4-1 and CD8α rapidly increased in pCG-GroEL vaccinated fish after challenge with E. tarda. Taking together, pCG-GroEL could elicit highly protective effects against E. tarda and induce strong immune response of flounder, suggesting that GroEL was a promising vaccine candidate.
authors.affiliation: Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Fuguo
authors.initials: F
authors.lastname: Liu
authors.affiliation: Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Xiaoqian
authors.initials: X
authors.lastname: Tang
authors.affiliation: Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Xiuzhen
authors.initials: X
authors.lastname: Sheng
authors.affiliation: Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xing
authors.affiliation: Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, No.1 Wenhai Road, Aoshanwei Town, Jimo, Qingdao 266071, China. Electronic address: wbzhan@ouc.edu.cn.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Zhan
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001428:Bacterial Vaccines / Q000276:immunology*; D018834:Chaperonin 60 / Q000276:immunology*; D004195:Disease Models, Animal; D020609:Edwardsiella tarda / Q000276:immunology; D004756:Enterobacteriaceae Infections / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay; D005393:Fish Diseases / Q000276:immunology*; D005432:Flounder / Q000276:immunology / Q000382:microbiology*; D005434:Flow Cytometry; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000276:immunology; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D018834:Chaperonin 60; D011994:Recombinant Proteins; D019444:Vaccines, DNA
keywords: DNA vaccine; Edwardsiella tarda; Flounder; Immune response; Molecular chaperone GroEL