CELL MEDIATED HEMOSTASIS

描述（申请人的逐字描述）：这背后的假设 建议是细胞，而不是蛋白质，指导凝血反应。 这一推论是：1）激活凝血的细胞定位 因子决定其在凝血级联中的功能;和2）特异性 不同细胞类型的特征，如特异性受体的存在， 确定细胞的抗凝血和促凝血特征。这些研究将 使用我们开发的基于细胞的凝固模型系统。我们有 研究提出了四个具体目标。第一个目标是审查 活化蛋白C对内皮细胞的功能与 其对磷脂囊泡或活化血小板的活性。这些研究 将使用具有切割位点突变的因子V分子。我们还将 看看因子V和因子V的裂解形式作为一种 活化蛋白C灭活因子VIII的辅因子。第二个目的 研究细胞组织因子的活性是如何被控制的。这些研究将 看看组织因子加密和解密，氧化剂的作用， 改变细胞组织因子活性，以及组织因子 途径抑制剂和抗凝血酶III在灭活因子VIla/组织中的作用 因子复合体第三个目标是研究哪些因素决定了失业率， 在活化的血小板上产生的凝血酶的量。这些研究将检查 限制血小板表面凝血酶生成的机制。第四 aim研究了在基于细胞的模型中产生的凝血酶的量 是否与体内稳定止血凝块的形成相关？这些研究 将检查纤维蛋白原的结构和对溶解的敏感性，以及 凝血酶激活的纤维蛋白溶解抑制剂的作用。

DESCRIPTION (Applicant's Description Verbatim): The hypothesis underlying this proposal is that cells, rather than proteins, direct the coagulation reactions. Corollaries of this are: 1) the cellular location of the activated coagulation factors determines their function in the coagulation cascade; and 2) specific features of different cell types, such as the presence of specific receptors, determine the anti- and pro-coagulant features of the cells. These studies will use a cell based model system of coagulation we have developed. We have proposed studies that fall within four specific aims. The first aim examines how the function of activated protein C on endothelial cells is different from its activity on phospholipid vesicles or activated platelets. These studies will use factor V molecules that have cleavage site mutations. We will also look at the ability of factor V and cleaved forms of factor V to act as a cofactor for activated protein C inactivation of factor VIII. The second aim examines how cellular tissue factor activity is controlled. These studies will look at tissue factor encryption and de-encryption, the role of oxidants in altering cellular tissue factor activity, and the roles of tissue factor pathway inhibitor and anti-thrombin Ill in inactivating the factor VIla/tissue factor complex. The third aim examines what factors determine the rate and amount of thrombin generated on activated platelets. These studies will examine mechanisms that limit thrombin generation on the platelet surface. The fourth aim examines how the amount of thrombin generated in the cell-based model correlates with formation of a stable hemostatic clot in vivo? These studies will examine fibrinogen structure and susceptibility to lysis as well as the role of thrombin activatable fibrinolysis inhibitor.