PLATELET-ENDOTHELIAL CELL INTERACTIONS

血小板-内皮细胞相互作用

• 批准号: 3344696
• 负责人: Eric Franklin Grabowski
• 金额: $ 14.21万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-01 至 1992-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3344696
• 关键词: anticoagulants; blood coagulation tests; blood viscosity; cardiovascular disorder chemotherapy; cardiovascular pharmacology; cell adhesion; cell cell interaction; coagulation factor VIII; eicosanoid metabolism; fluorescence microscopy; granulocyte; human subject; immunofluorescence technique; leukocytes; phantom model; platelet aggregation; prostacyclins; prostaglandin E; prostaglandin inhibitors; radioimmunoassay; thrombosis; tissue /cell culture; vascular endothelium; vasculitis; video recording system

Clinical experience over the last two decades has shown that antiplatelet--therapy is often not effective in the treatment of arterial thrombotic disorders. Patients on aspirin and other agents which impair platelet cyclooxygenase and the platelet release reaction continue to suffer recurrent episodes of myocardial ischemia or recurrent stroke. We therefore hypothesize that some arterial thrombotic disorders are in part due to the procoagulant activity (PCA) of a stimulated, inflammed or injured vessel wall. This view is in keeping with recent in vitro data that vascular endothelium, when stimulated by inflammatory/immune mediators such as interleukin-l (IL-l), tissue necrosis factor (TNF), lymphotoxin or hepatic stimulating factor, can become prothrombotic by generating, for example, tissue factor and molecules adhesive for granulocytes. Simultaneously, vasculitis and/or vessel wall injury may diminish the production of substances of arachidonate (prostacyclin and PGE2) and non-arachidonate (endothelial cell relaxing factor) metabolism which normally modulate leukocyte-platelet adhesion/aggregation. The experimental approach taken here to evaluate this hypothesis is to simulate in vitro flow through a microvessel. We do so by utilizing a flow chamber which incorporates whole blood, arterial-like shear rates, a flow path of thickness 290 um, and in situ epifluorescence video- microscopy of leukocyte-platelet adhesion/aggregation to a defined injury site on an endothelial cell monolayer. Our aims include 1) establishing the effects of flow (shear rate and shear stress) on PCA; 2) determining the dependence on flow of granulocyte adhesion to non-injured endothelium; and 3) determining the flow dependence of leukocyte-platelet adhesion/aggregation to a site of defined injury to endothelium. PCA will be measured with flowing, cell- free media and a radiometric assay for Factor Xa conversion. For imaging purposes,platelets will be labelled with a fluorescein- conjugated monoclonal antibody (TAB) to glycoprotein IIB, while monocyte-granulocytes will be labelled with a rhodamine-conjugated monoclonal antibody directed against the Mo5 antigen. In particular, we seek a rational basis for the use of anticoagulant therapy in certain cases of arterial thrombosis.

过去二十年来临床经验表明 抗血小板 - 治疗通常在治疗中无效 动脉血栓性疾病。 阿司匹林和其他患者 损害血小板环氧合酶和血小板的药物 释放反应继续遭受反复发作的发作 心肌缺血或复发性中风。 因此，我们假设 某些动脉血栓性疾病部分是由于 刺激，发炎或受伤的proc凝活性（PCA） 船墙。 这种观点与最近的体外数据保持一致 当炎症/免疫刺激时，那个血管内皮 介体，例如白介素-L（IL-L），组织坏死因子 （TNF），淋巴毒素或肝刺激因子，可以变成 通过产生例如组织因子和 分子粘合剂用于粒细胞。 同时，血管炎 和/或容器壁损伤可能会减少物质的产生 蛛网酸（前列环蛋白和PGE2）和非弧菌酸盐 （内皮细胞松弛因子）代谢通常 调节白细胞 - 血小板粘附/聚集。 实验 在此评估这一假设的方法是模拟 体外流过微血管。 我们通过使用流量来做到这一点 室内包含全血，类似动脉样剪切速率， 厚度为290 um的流动路径，原位表面荧光视频 - 白细胞 - 血小板粘附/聚集到定义的显微镜 内皮细胞单层上的损伤部位。 我们的目标包括1） 建立流量（剪切速率和剪切应力）对 PCA; 2）确定对粒细胞粘附流动的依赖性 到无损伤的内皮； 3）确定流动依赖性 白细胞 - 血小板粘附/聚集到定义的位点 内皮受伤。 PCA将通过流动的细胞来测量 免费介质和用于因子XA转换的辐射测定。 为了 成像目的，血小板将用荧光素标记 共轭的单克隆抗体（TAB）与糖蛋白IIB，而 单核细胞颗粒细胞将用若丹明偶联的标签标记 针对MO5抗原的单克隆抗体。 在 特别是，我们为使用抗凝剂寻求合理的基础 在某些动脉血栓形成的情况下进行治疗。