弓形虫MIC8基因对弓形虫病的免疫保护性研究

Toxoplasma gondii MIC8 gene has immunoprotective effect on toxoplasmosis

目的观察弓形虫MIC8基因对弓形虫病免疫保护性的效果。方法用PCR方法扩增弓形虫MIC8基因,定向克隆到真核表达质粒pEGFP-N1中,构建重组表达载体pEGFP-MIC8;MIC8-EGFP转染293T细胞,荧光显微镜观察表达情况;然后分别用质粒pEGFP-MIC8、pEGFP-N1空载体及生理盐水肌肉注射免疫BALB/c小鼠,共免疫3次,末次免疫3周后用弓形虫RH株速殖子感染免疫小鼠。结果 PCR扩增弓形虫MIC基因序列正确,构建的重组表达载体pEGFP-MIC8鉴定正确,荧光显微镜下观察到重组质粒能够在293T细胞中表达。弓形虫攻击感染后,质粒pEGFP-MIC8免疫小鼠与对照组相比,小鼠的存活时间有一定的延长。结论构建的真核表达重组质粒pEGFP-MIC8对抗击弓形虫攻击感染能够激发一定的免疫保护性。

Objective Investigate immunoprotective effects of T.gondii microneme 8（MIC8） on toxoplasmosis.Methods MIC8 gene fragment was amplified by PCR and cloned into pEGFP-N1 to generate eukaryotic expression construct pEGFP-MIC8;GFP tagged MIC8 protein was expressed in the 293 cells by transfection and observed using a fluorescence microscope;Plasmid pEGFP-MIC8,pEGFP-N1 and NS were injected into BALB/c mice muscle three times.Each injected mouse was challenged with tachyzoites of T.gondii after the last immunization and viability was determined in three weeks.Results Survival time of MIC8 immunized mice was prolonged in comparison with the control group when infected by T.gondii.Conclusion MIC8 could trigger immmuno-protection when responding to T.gondii infections.