CELL MEDIATED HEMOSTASIS

凝血蛋白之间的复杂相互作用最初是 被描述为一场瀑布。该模型已经过改进，以考虑到 凝血因子组成的复合体中凝血因子的组织 蛋白水解酶及其底物酶原蛋白都结合在一个膜上- 相关蛋白辅因子。细胞内蛋白质之间的相互作用 复合体为凝血提供了一个水平的调节。我们建议 在血液凝固方面，至少还有另外两种水平的调节。 其中一个层面涉及凝血之间活化蛋白的运输 复合体。第二个层面涉及细胞的积极参与 调节凝血所需的关键因子的量。这项建议 检查与止血有关的重要细胞相互作用。血小板 单核细胞将被用作表面组装三种凝集 复合体：组织因子-V11a(Tf-VIIa)、因子VIIa-因子IXa (Xase)和凝血因子Va-凝血因子Xa(Llase)。血小板迅速定位于 并提供主要塞子以及用于 组装纤维蛋白插头。单核细胞将被检查，因为它们是一种 模型中含有Tf的细胞，并且它们还具有Tf不依赖的机制 激活因子X.EE假设细胞之间的相互作用 血小板和转铁蛋白细胞在凝血过程中的相互作用 在这些细胞上组装的复合体。我们认为，这一切的总和 促凝血剂系统的类型大于其各部分的总和，并且 只对个别部分进行研究不会产生一个适当的模型 活体止血。因此，这笔赠款的总体目标是审查 Tf-V11a、Xase和Liase在体外的协同活性和相互作用 用动力学分析和免疫化学方法检测血小板和单核细胞。一个 对这一相对简单的三种蛋白质复合体系统的理解 在两种不同的细胞类型上，应该允许我们对其他细胞蛋白质进行建模 在凝聚中非常重要的相互作用，以努力扩大我们的 体内止血的概念和我们对血栓形成和血栓形成的理解 大出血。

The complex interactions among blood coagulation proteins was initially described as a cascade. That model has been refined to take into account the organization of coagulation factors into complexes that consist of a protease and its substrate zymogen protein both bound to a membrane- associated protein cofactor. The interactions between proteins within the complex provide one level of regulation for coagulation. We suggest that there are at least two other levels of regulation in blood coagulation. One level involves the traffic of activated proteins between coagulation complexes. A second level involves the active participation of cells to regulate the amounts of key factors needed for coagulation. This proposal examines important cellular interactions involved in hemostasis. Platelets and monocytes will be used as surfaces to assemble three coagulation complexes: tissue factor-factor Vlla (TF-VIIa), factor VIIIa-factor IXa (Xase), and factor Va-factor Xa (llase). Platelets quickly localize at the site of an injury and provide a primary plug as well as a surface for assembling a fibrin plug. Monocytes will be examined because they are a model TF-containing cell, and they also have a TF independent mechanism for activating factor X. Ee hypothesize that cellular interactions between platelets and TF-bearing cells mediate interactions between the coagulation complexes assembled on these cells. We believe that the totality of this type of procoagulant system is more than the sum of its parts, and that a study of only the individual parts will not lead to an adequate model of in vivo hemostasis. So the overall goal of this grant is to examine the concerted and interrelated activity of TF-Vlla, Xase, and liase on isolated platelets and monocytes by kinetic analysis and immunochemical methods. An understanding of this relatively simple system of three protein complexes on two different cell types should allow us to model other cell-protein interactions that are important in coagulation in an effort to expand our concept of in vivo hemostasis and our understanding of thrombosis and hemorrhage.