日本血吸虫成虫低密度脂蛋白受体研究

Study on Low Density Lipoprotein Receptor of Adult Schistosoma japonicum

目的 研究日本血吸虫成虫低密度脂蛋白受体 ,为以后的疫苗研究提供依据。 方法 自人工感染家兔的肠系膜下静脉取日本血吸虫成虫 ,用非离子去污剂TritonX 10 0抽提出日本血吸虫成虫表膜蛋白 ,反相高效液相色谱(HPLC)进行分离纯化后 ,收集各主要分离蛋白峰 ,以12 5I标记的人血浆低密度脂蛋白 (LDL)作为放射性配体 ,经放射性自显影及放射性受体配体结合分析鉴定能与人血浆12 5I LDL特异结合的蛋白。并以SDS PAGE及等电聚焦电泳确定其纯度、分子量及等电点。 结果 在日本血吸虫雌、雄成虫虫体表膜均存在可与人血浆12 5I LDL特异性结合的蛋白分子 ,此蛋白是日本血吸虫成虫低密度脂蛋白受体 ,在HPLC上保留时间为 10 .5min ,SDS PAGE显示其分子量约 6 0～6 5kDa ,等电点为 6 .7。 结论 日本血吸虫雌。

Objective To provide a theoretical basis for the study of vaccines against Schistosoma japonicum , the receptor for human LDL in the tegument of adult Schistosoma japonicum was investigated. Methods Proteins existed in adult Schistosoma japonicum membrane were extracted by Triton X-100 and purified through reverse-phase high performance liquid chromatography (HPLC),and the main protein peaks were then collected separately. 125 I-LDL of human plasma as the ligand, through the radioautography and radioligand binding assay, the protein which can bind human serum 125 I-LDL specifically was identified. The molecular weight and IEF were detected by SDS-PAGE. Results According to the radioautography and radioligand binding assay, a protein with retention time of 10.5 min was proved to be able to bind human serum 125 I-LDL specifically. SDS-PAGE revealed that the molecular weight of the purified protein is 60-65 kDa, and its IEF is 6.7. Conclusion LDL binding protein may exist on the surface of both male and female adult Schistosoma japonicum with the function of obtaining cholesterol from host circulating system.