MOBILITY AND ADHESION OF SICKLE MEMBRANE COMPONENTS

镰状膜组件的流动性和粘附性

• 批准号: 5213157
• 负责人: DAVID E GOLAN
• 金额: --
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/5213157
• 关键词: cell adhesion; cell motility; electron microscopy; erythrocyte membrane; fluorescent dye /probe; glycophorin; hemoglobin Ss; human subject; lasers; lipid transport; macrophage; membrane lipids; membrane proteins; monocyte; phosphatidylserines; phospholipids; polymerization; protein transport; sickle cell anemia; sickle cell crisis; tissue /cell culture; vascular endothelium; video microscopy

Interactions between the human red blood cell (RBC) membrane and its intracellular and extracellular environment mediate both normal RBC homeostasis and abnormal RBC pathology in the circulation. Polymerization of hemoglobin S within sickle RBCs leads to a spectrum of membrane derangements, including changes in protein-protein and protein- lipid interactions, that affect the mobility and surface distribution of the major transmembrane proteins, glycophorin and band 3. Alterations in the surface distribution of glycophorin-bearing negative charges may influence sickle RBC adherence to vascular endothelial cells (ECs), which may, in turn, initiate vaso-occlusive crisis. Formation of band 3 aggregates in sickle RBC membranes may promote the binding of autologous antibody to these cells, facilitating their premature removal by monocytes and macrophages. Abnormal exposure of phosphatidylserine at the surface of sickle RBCs may also mediate adherence to monocytes and macrophages. In this proposal high-speed laser and video microscopy techniques are used to measure the lateral mobility, rotational mobility, and surface distribution of transmembrane proteins and lipids in individual sickle RBC membranes and in the membranes of sickle RBCs adherent to ECs in culture, to peripheral blood monocytes, and to immobilized plasma proteins that may be important in facilitating sickle RBC-EC adhesion. These proteins include fibrin, fibrinogen, fibronectin, thrombospondin, vitronectin, and von Willebrand factor. We aim to test the hypotheses that: 1) specific abnormalities in sickle RBC band 3, glycophorin, and phospholipid mobility and surface distribution correlate, at the level of individual sickle RBCs, with increased binding of autologous antibody and increased adherence to monocytes, macrophages, and ECs; and 2) specific plasma proteins serve as important mediators of sickle RBC-EC adhesion. Results from these studies are expected to elucidate molecular defects in the sickle RBC membrane that are directly involved in the pathophysiology of sickle RBC hemolysis and vaso- occlusive crisis.

人红细胞（RBC）膜与其 细胞内和细胞外环境介导正常红细胞 体内平衡和循环中的异常RBC病理学。 镰状红细胞内血红蛋白S的聚合导致一系列的 膜紊乱，包括蛋白-蛋白和蛋白- 脂质相互作用，影响流动性和表面分布， 主要的跨膜蛋白，血型糖蛋白和带3。 改变 在带有血型糖蛋白的负电荷的表面分布中， 影响镰状红细胞与血管内皮细胞（EC）的粘附， 可能反过来引发血管闭塞危象。 第三条乐队的形成 镰状红细胞膜中的聚集物可能促进自体红细胞膜结合。 这些细胞的抗体，促进其过早清除， 单核细胞和巨噬细胞。 磷脂酰丝氨酸的异常暴露， 镰状红细胞的表面也可介导对单核细胞的粘附， 巨噬细胞 在这项提案中，高速激光和视频显微镜 技术被用来测量横向迁移率，旋转迁移率， 和跨膜蛋白和脂质的表面分布 单个镰状红细胞膜和镰状红细胞膜中 粘附于培养物中的EC，粘附于外周血单核细胞，以及粘附于 固定的血浆蛋白质，可能是重要的，在促进镰刀 RBC-EC粘附。 这些蛋白质包括纤维蛋白、纤维蛋白原、纤连蛋白， 血小板反应蛋白、玻连蛋白和血管性血友病因子。 我们的目标是测试 假设：1）镰状红细胞带3的特异性异常， 血型糖蛋白、磷脂迁移率和表面分布 在单个镰状红细胞水平上， 自体抗体和单核细胞，巨噬细胞， 和EC;和2）特定的血浆蛋白作为重要的介质， 镰状红细胞-内皮细胞粘附。 这些研究的结果预计将 阐明镰状红细胞膜中的分子缺陷， 参与镰状红细胞溶血和血管紧张素Ⅱ的病理生理学， 闭塞性危象