重组日本血吸虫铁蛋白的表达纯化及诱导小鼠保护性免疫研究

目的　表达、纯化重组日本血吸虫铁蛋白 ,观察其免疫小鼠后抗日本血吸虫的免疫保护作用。方法　用基因重组技术 ,将日本血吸虫铁蛋白基因亚克隆至表达载体 pGMC上 ;在IPTG诱导下 ,重组日本血吸虫铁蛋白得到高效表达 ;用电泳层析法分离纯化日本血吸虫铁蛋白 ;用SDS -PAGE和Western -blot鉴定表达纯化产物 ;用纯化的重组铁蛋白免疫小鼠三次 ,分别在 0、2、4周进行。第 6周每鼠经腹部感染 4 0± 1条日本血吸虫尾蚴。 4 2天后剖杀冲虫 ,计数虫数及肝卵数。结果　纯化的重组铁蛋白分子量为 4 0kD ,具有较好的免疫原性 ,能被日本血吸虫感染兔血清识别。与对照组相比 ,纯化重组铁蛋白免疫小鼠组的减虫率为 2 4 5 % ,减卵率为 4 5 8%。结论　重组日本血吸虫铁蛋白不仅在大肠杆菌中得到高效表达 ,而且纯化的铁蛋白分子能诱导抗日本血吸虫病的保护性免疫。

Schistosoma japonicum recombinant ferritin:expression,purification and its protective immunity against Schistosoma japonicum in mice

Objective To express and purify recombinant Schistosoma japonicum ferritin(rsjferritin)and to explore the protective immunity against Schistosoma japonicum induced by the protein in mice.Methods The ferritin gene was subcloned into the expression vector pGMC.The rsjferritin was expressed at a high level in E.coli 2566 induced by IPTG.Purify and identify using electrophoretic chromatography,SDS-PAGE and Western-blot.Kunming mice were immunized subcutaneously three times(0,2,4 weeks)with rsjferritin.Each mouse was challenged with 40±1 cercariae.6 weeks later the mice were killed,the worms and the liver eggs were counted.Results The purified rsjferritin's molecular weight was 40kD,and it possessed good antigenic activity and could be recognized by the rabbit sera infected with Schistosoma japonicum.Compared with the control groups,the worm reduction rate and eggs per gram liver reduction rate in experimental group were 24.5% and 45.8% respectively.Conclusion The rsjferritin has been expressed high efficiently in E.coli,and it can induce a protective immunity against Shistosoma japonicum in mice.