Rumjanek F D, Pereira M A, Silveira A M
Mol Biochem Parasitol. 1985 Jan;14(1):63-73. doi: 10.1016/0166-6851(85)90106-9.
After contact with human serum, a series of proteins become exposed on the surface membranes of schistosomula of Schistosoma mansoni as revealed by radioiodination of the intact parasites. Among the proteins, a doublet (Mr 45 000) is particularly prominent. These doublet proteins, which are believed to be parasite-derived, become apparent after a very short time of incubation with human serum (10 min or less) and are expressed on the surface membranes after contact with a high molecular weight component of human serum (Mr greater than 80 000). Pretreatment of the parasites with 1.25 mM colchicine or fixation with 2% glutaraldehyde does not prevent the serum-induced expression of the doublet proteins. Extraction of the parasites with chloroform:methanol 2:1 (v/v), however, blocks the human serum effect. Affinity chromatography using immobilized low density lipoproteins (LDL) from human serum shows a tight binding between the 125I-labelled 45 kDa doublet to the LDL. The possible role of the 45 kDa doublet as a receptor for LDL is discussed.
与人体血清接触后，通过对完整寄生虫进行放射性碘化发现，曼氏血吸虫童虫的表面膜上会暴露出一系列蛋白质。在这些蛋白质中，一个双峰蛋白（分子量45000）尤为突出。这些双峰蛋白被认为源自寄生虫，在与人体血清孵育很短时间（10分钟或更短）后就会显现，并在与人体血清的高分子量成分（分子量大于80000）接触后表达于表面膜上。用1.25 mM秋水仙碱预处理寄生虫或用2%戊二醛固定，均不能阻止血清诱导的双峰蛋白表达。然而，用氯仿：甲醇2:1（v/v）提取寄生虫会阻断人体血清的作用。使用固定化的人血清低密度脂蛋白（LDL）进行亲和层析显示，125I标记的45 kDa双峰蛋白与LDL之间有紧密结合。文中讨论了45 kDa双峰蛋白作为LDL受体的可能作用。
