摘要
为制备大肠杆菌(E.coli)菌蜕并研究其免疫原性,本研究将带有裂解基因E的质粒pHH43转化致病性鸭源E.coli O78,构建获得E.coli O78/pHH43重组菌。于不同培养温度下研究重组菌E裂解蛋白表达所介导的宿主菌的裂解情况,结果显示在42℃培养时最佳诱导时间为4h,约90%的重组菌被裂解失活,以冻干法及添加庆大霉素完全灭活未裂解的细菌后制备"菌蜕疫苗"。雏鸭免疫试验表明,接种E.coli O78/pHH43菌蜕两周后免疫雏鸭可产生对同源强毒菌株致死剂量攻击的免疫保护。比较E.coli O78/pHH43菌蜕与甲醛灭活的同株E.coli所诱导的免疫保护效果,结果免疫保护率分别为87.5%和75%,表明菌蜕比甲醛灭活法能更有效地诱导机体的特异性免疫应答。
To evaluate the immunogenicity of bacterial ghosts of Escherichia coli strain serotype O78 isolated from infected ducklings,recombinant strains of E. coli serotype O78 were constructed by transformation of pHH43 containing lysis gene E into the baterial cells and cultured at different temperatures for probing the lysis effects induced by the expressed E protein. Approximate 90% of transformed bacteria were lysed after inducing at 42 ℃ for 4 hours. The recombinant bacteria were successfully transformed into the bacterial ghost after completely inactivated by gentamycin and lyophilization. Ducklings were vaccinated with these ＂ghosts＂ and 87.5% of the ducklings were protected from challenge by lethal dose of the live E. coli two weeks after immunization. The immunoprotection rate triggered by E. coli O78 ghost was slightly higher than that of inactivated homologous E. coli （75%）. It is suggested that the bacteria ghost could more effectively induce the specific immune response than formaldehyde in activated bacteria.
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2010年第9期712-715,共4页
Chinese Journal of Preventive Veterinary Medicine
基金
广东省科技攻关项目(2005A20401004
2006A20301002)
关键词
大肠杆菌
菌蜕
免疫原性
Eshcerichis coli
bacterial ghosts
Immunogenicity
