【作者】 王荣华； 刘小燕； 曾令兵； 肖调义；

【Author】 Wang Rong-hua;Liu Xiao-yan;Zeng Ling-bing;Xiao Tiao-yi;College of animal science,Hunan Agricultural University;Yangtze River Fisheries Research Institute,Chinese Academy of Fishery Sciences;

【机构】 湖南农业大学动物科学技术学院； 中国水产科学研究院长江水产研究所；

【摘要】 本研究首次将外源裂解基因E导入鮰爱德华氏菌,通过诱导表达制备了鮰爱德华氏菌菌蜕疫苗(Edwardsiella ictaluri ghost,EIG);应用该疫苗注射免疫健康斑点叉尾鮰,研究免疫后其血清凝集效价变化情况与免疫保护效果。诱导结束后,电子显微镜研究发现,菌蜕细胞内无细胞质等内含物,细胞表面有100~200nm直径的孔洞,裂解效率达到99.997%,且冷冻干燥后,涂布平板无活菌生长;免疫后,EIG组血清凝集效价迅速升高,且在第21天达到峰值1:682.67,极显著高于对照组(P<0.01)。且攻毒后,EIG组相对免疫保护率达到89.3%。结果表明:EIG能诱导斑点叉尾鮰产生强烈免疫应答反应,具有很好的免疫保护效果,有望成为一种安全、高效的预防斑点叉尾鮰肠道败血症的方法。更多还原

【Abstract】 In this study, Edwardsiella ictaluri ghosts(EIG) have been generated for the first time bycontrolled expression of exogenous lysis gene E, and it was used as antigen to immunize channel catfish via intraperitoneal injection. After immunized, the serum agglutinating antibody titers and relative percent survival(RPS) have been detected. After induction, Electron microscopic analysis of protein E-lysed E.ictaluri cells revealed no gross alterations in cellular morphology and a pores ranging from 100 to 200 nm in diameter were observed in E.ictaluri ghosts by scanning electron microscopy. The efficiency of ghost induction was 99.997% at the end of lysis process, and there is no bacterial growth in BHI plate after lyophilized. After immunized, the serum agglutinating antibody titers were very increased significantly, and peaked at 1:682.67 at day 21 post-immunization. The result of challenge test with E.ictaluri revealed that the relative percent survival(RPS) of the immunized fish was 89.3%. The results here demonstrated that the inactivated E.ictaluri has effective immunogenicity, and the immunized channel catfish acquired the ability against the infection of E.ictaluri, which laid a base for the further study on the immunoprophylaxis against the infection of E.ictaluri in channel catfish. As a nonliving whole cell envelope preparation, EIG may provide an ideal alternative to pathogen-based vaccines against ESC in aquaculture.更多还原