日本血吸虫卵黄铁蛋白基因免疫小鼠的保护性研究

STUDY ON THE PROTECTIVE IMMUNITY IN MICE BY DNA VACCINATION WITH RECOMBINANT PLASMID ENCODING SCHISTOSOMA JAPONICUM YOLK FERRITIN

目的 研究日本血吸虫卵黄铁蛋白基因 DNA免疫小鼠诱导的保护性免疫力。方法 将构建的日本血吸虫卵黄铁蛋白基因真核表达重组质粒 p L XSN- Fer l经左后腿肌肉注射 BAL B/ c小鼠 ,共免疫 2次 ,间隔 2周。末次免疫后 5周以血吸虫尾蚴攻击感染 ,攻击感染后 6周计数成虫负荷及肝组织虫卵数和死亡卵百分比。设空质粒免疫组为对照组。结果 p L XSN- Fer l免疫小鼠 ,诱生的Ig G亚类主要是 Ig G2 a和 Ig G2 b;免疫组可产生较高水平的 Ig A和 IFN- γ应答。 p L XSN- Fer l免疫小鼠诱生一定程度的减虫率 34 .0 8% ,减卵率 36 .83% ,死亡卵百分比为 30 .13%。结论 p L XSN-Fer l免疫小鼠能产生较明显的保护性免疫力 ,值得进一步深入研究。

Objective To investigate the immune efficacy of DNA vaccination in mice against yolk ferritin of Chinese Schistosoma japonicum. Methods BALB/c mice were vaccinated by each quadriceps muscle of left leg with pLXSN-Ferl encoding yolk ferritin gene of Chinese Schistosoma japonicum. Each group was immunized twice with 2wk interval. Mice vaccinated with pLXSN blank vector served as control. Mice were challenged five weeks after final DNA boosting by percutaneous infection with cercariae. Six weeks after infection the mice were perfused. Worm burden, eggs in liver and dead eggs were counted. Results Immunized mice produced predominantly IgG2a and IgG2b antibodies. Mice vaccinated with pLXSN-Ferl also produced IgA and IFN-γ. Immunization with pLXSN-Ferl could confer significant worm reduction rate 34 08%, egg reduction rate 36 83%, and dead egg rate 30 13%. Conclusion DNA vaccination with pLXSN-Ferl could induce protective immunity in BALB/c mice significantly. It is worth further research.