诱导型一氧化氮合酶在不同虫期日本血吸虫虫体中的表达

Distribution of Inducible Nitric Oxide Synthase in Different Stages of Schistosoma japonicum

目的 了解日本血吸虫不同虫期诱导型一氧化氮合酶 (iNOS)的表达及其在体内的分布。 方法 收集日本血吸虫成虫制成冰冻切片 ,将含胞蚴、尾蚴的感染性钉螺和含成熟虫卵的小鼠肝脏制成石蜡切片 ,用免疫荧光法检测成虫、胞蚴、尾蚴以及毛蚴中的iNOS ,并观察该酶在各期虫体内的分布 ;用蛋白质印迹法 (Westernblotting)检测成虫匀浆中的可溶性蛋白是否具抗iNOS多抗的可溶性蛋白。 结果 组织切片免疫荧光结果显示 ,特异性黄绿色荧光主要分布于成虫紧贴皮层下组织处、毛蚴的表层和腺体中以及胞蚴和尾蚴的体表 ;Westernblotting结果表明 ,成虫蛋白中出现 1条明显的被抗iNOS抗体识别的特异性反应条带 ,其相对分子质量 (Mr)为 2 10 0 0 0。 结论 日本血吸虫成虫及不同虫期幼虫均有类iNOS的蛋白表达。

Objective To study the presence of iNOS in Schistosoma japonicum and demonstrate its distribution in different stages of this schistosome. Methods Cryostat sections for adult worms and paraffin sections for eggs in the liver of infected mouse, sporocysts and cercariae in snails were prepared, immunofluorescent test was performed to detect the presence of iNOS in adult worms, sporocysts, cercariae and miracidium, the distribution of this enzyme was observed in different stages of Schistosoma japonicum. Western blotting was used to further demonstrate the immunoreactivity to iNOS in adult worms. Results The results of immunofluorescent test showed that specific yellow- green fluorescence was mainly among subtugment of adult worms. Positive staining was also distributed on the surface of miracidium and its glands. For both sporocysts and cercariae, the majority of fluorescence was on their surface. Anti-iNOS antibody could recognize an apparent specific band in Western blotting of adult worm proteins, with a of Mr 210 000. Conclusion There is an expression of iNOS-like enzyme in Schistosoma japonicum.