人红细胞膜CD59的分离及对依赖补体血小板损伤的保护

Fractionation of CD59 from human erythrocyte membrane and protection on complement dependent platelet injury

目的研究补体调节蛋白ＣＤ５９通过阻止补体攻膜复合物（ＭＡＣ）的形成发挥其对依赖补体血小板损伤的保护作用。方法用连续柱层析从眼镜蛇粗毒中分离纯化出眼镜蛇毒因子（ＣＶＦ）。人红细胞膜经低渗破膜、超滤、木瓜蛋白酶消化、正丁醇抽提和连续柱层析分离纯化出补体调节蛋白ＣＤ５９。用ＣｈｒｏｎｏＬｏｇ型血小板聚集仪测定血小板变形、聚集和ＡＴＰ释放反应。结果预先加入ＣＤ５９可抑制ＣＶＦ引起的大白鼠血小板变形和ＡＴＰ释放，不影响ＣＶＦ引起的血小板聚集及粘附性增加。结论血小板膜表面形成的ＭＡＣ是补体激活引起血小板变形和ＡＴＰ释放的关键。

AIM To study the protective action of complement regulatory protein CD59 on complement dependent platelet injury by preventing the formation of membrane attack complex (MAC). METHODS Cobra venom factor (CVF) was separated and purified by successive chromatography from crude cobra venom. CD59 was fractionated and purified by low osmosis preparation, ultrafiltration, papain digestion, n butanol abstrct and successive chromatography from the membrane of human erythrocytes. Platelet shape change, aggregation and ATP release were detected by Chrono Log platelet aggregation instrument. RESULTS CD59 with inhibition of the formation of MAC on the cellular membrane can prevent platelet shape change and ATP release induced by CVF but unaffect platelet aggregation and adhesiveness. CONCLUSION MAC plays an important part in platelet shape change and ATP release induced by activation of complements. CD59 has protective action on complement dependent platelet injury.