Protein C Translational Studies

Prowess III期临床试验表明，激活的蛋白C(APC)在以下方面降低了死亡率 单纯的抗凝剂和单纯的抗炎药都不起作用。因此，APC注入到 人类和动物一样，除了抗凝作用外，还具有拯救生命的活动。最近的体外试验 体内研究支持一种新的范式，即APC发挥保护性抗炎和抗细胞凋亡作用 蛋白水解酶激活受体1激活机制对细胞的直接作用 (PAR1)与内皮蛋白C受体(EPCR)结合的APC。APC的抗炎抗细胞凋亡作用 在体内的活性可能源于它改变基因表达谱的能力。炎症和 细胞凋亡参与血栓形成的发病机制。因此，重组(R)APC有望用于治疗 血栓性疾病。我们将准备大量的小鼠APC突变体，并将其作为潜在的研究 使用小鼠模型来确定其体内活性的治疗药物。APC的抗凝血活性和 APC在体外对细胞的直接作用将在依赖EPCR和依赖PAR1的研究中确定 APC抑制细胞凋亡和改变内皮细胞基因表达的能力。评价APC在体内的作用 活性，我们将使用小鼠模型，并在体内测定野生型和突变型APC的以下内容 性质：1)抗血栓活性；2)抗炎活性；3)血管内皮细胞基因表达改变 没有受伤。在初步工作中，我们鉴定了两个抗凝血活性缺乏的APC突变体 体外抗细胞凋亡活性正常。这样的APC变体可以提供APC的有益的EPCR依赖的， PAR-1依赖的对细胞的直接作用降低了严重出血的风险。因为APC保护性地 针对凝血因子和细胞表面受体，该项目的结果可能直接导致 开发用于治疗各种血栓性疾病的新型多功能药物。

The PROWESS phase III clinical trial showed that activated protein C (APC) reduced mortality where neither purely anticoagulant nor purely anti-inflammatory agents were effective. Thus, APC infused into humans, as in animals, exerts life-saving activities in addition to its anticoagulant actions. Recent in vitro and in vivo studies support a new paradigm in which APC exerts protective anti-inflammatory and antiapoptotic direct effects on cells via mechanisms involving activation of Protease Activated Receptor 1 (PAR1) by APC bound to Endothelial Protein C Receptor (EPCR). APC's anti-inflammatory and antiapoptotic in vivo activities may result from its ability to alter gene expression profiles. Both inflammation and apoptosis contribute to the pathogenesis of thrombosis. Thus, recombinant (r) APC is promising for treating thrombotic disorders. We will prepare numerous murine APC mutants and study them as potential therapeutic agents using murine models to define their in vivo activities. APC's anticoagulant activity and APC's direct effects on cells in vitro will be determined in studies of the EPCR-dependent, PAR1-dependent abilities of APC to inhibit apoptosis and to alter endothelial cell gene expression. To assess APC's in vivo activities, we will use murine models and determine for wild type and mutant APC's the following in vivo properties: 1) antithrombotic activity; 2) anti-inflammatory activity; and 3) alteration of gene expression in the absence of injury. In preliminary work, we identified two APC mutants deficient in anticoagulant activity with normal in vitro anti-apoptotic activity. Such APC variants may provide APC's beneficial EPCR-dependent, PAR 1-dependent direct effects on cells with reduced risk of serious bleeding. Because APC protectively targets both clotting factors and cell surface receptors, the results of this project may lead directly to development of novel, multi-functional agents for treatment of a variety of thrombotic disorders.