title: Protective immunity against infectious spleen and kidney necrosis virus induced by immunization with DNA plasmid containing mcp gene in Chinese perch Siniperca chuatsi.
abstract: Infectious spleen and kidney necrosis virus (ISKNV) is the causative agent of a disease leading to high mortality and economic losses in Chinese perch, Siniperca chuatsi. There is an urgent need to develop an effective vaccine against this fatal disease. In this study, the mcp gene encoding the major capsid protein, the predominant structural component of the iridovirus particles, was cloned into a eukaryotic expression vector pcDNA3.1+, and the recombinant plasmid, designated as pcMCP, was constructed. Expression of the mcp gene was confirmed in transfected cells and muscle tissues of vaccinated fish by RT-PCR, immunodot blot and western blot. Immune response was induced by intramuscular injection of Chinese perch with pcMCP added QCDC adjuvant. The expression levels of type I IFN system genes including IRF-7, IRAK1, Mx and Viperin were up-regulated at 6 h, and reached a peak at 48 h. In addition, there was a second peak of the expression levels of IRF-7 and Mx gene on the 21st day post-vaccination. Before the 21st day post-vaccination, the levels of IgM did not show a significant difference among all groups, but there was a remarkable increase on the 28th day post-vaccination. The relative percent survival (RPS) of Chinese perch vaccinated with pcMCP added QCDC adjuvant was 80% in a challenge trial on the 28th day post-vaccination. Moreover, real-time PCR demonstrated that the levels of viral load in the dead fish of the vaccinated group were significantly higher than those in mock-vaccinated fish. Together, these results indicate that pcMCP is a potential candidate DNA vaccine against ISKNV disease.
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Xiaozhe
authors.initials: X
authors.lastname: Fu
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Ningqiu
authors.initials: N
authors.lastname: Li
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Lin
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China.
authors.forename: Huizhi
authors.initials: H
authors.lastname: Guo
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Defeng
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Liu
authors.affiliation: Pearl River Fishery Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangzhou 510380, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China. Electronic address: wushuqin001@21cn.com.
authors.forename: Shuqin
authors.initials: S
authors.lastname: Wu
mesh_terms: D056704:Adaptive Immunity; D000276:Adjuvants, Immunologic / Q000627:therapeutic use; D000818:Animals; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D003001:Cloning, Molecular; D004266:DNA Virus Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D005393:Fish Diseases / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D007113:Immunity, Innate; D007497:Iridoviridae / Q000276:immunology*; D010473:Perciformes; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019444:Vaccines, DNA / Q000008:administration & dosage; D014765:Viral Vaccines / Q000008:administration & dosage*
chemical_list: D000276:Adjuvants, Immunologic; D036022:Capsid Proteins; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D014765:Viral Vaccines; C081132:major capsid protein, Iridovirus
keywords: DNA vaccine; Infectious spleen and kidney necrosis virus; Major capsid protein; Siniperca chuatsi