Platelet CLEC-2 in Arterial Thrombosis

动脉血栓形成中的血小板 CLEC-2

基本信息

批准号：
10652286
负责人：
Lijun Xia
金额：
$ 43.7万
依托单位：
OKLAHOMA MEDICAL RESEARCH FOUNDATION
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10652286
关键词：
Address Adhesions Adverse effects Antiplatelet Drugs Arteries Aspirin Binding Biological Bleeding time procedure Blood Cells Blood Platelets Blood Vessels Blood flow C-Type Lectins Carbohydrates Cessation of life Chimeric Proteins Clinical Coagulation Process Cytoplasmic Tail Data Development Endothelium Exhibits Extracellular Domain FDA approved Fc domain Glycopeptides Glycoproteins Growth Hemorrhage Hemostatic function Human ITAM Immunoglobulin G In Vitro Integrins Lectin Life Ligands Link Mediating Medicine Modeling Mus Myocardial Infarction Myocardial Ischemia Pathogenesis Pathologic Pathway interactions Patients Platelet Activation Platelet Glycoproteins Platelet aggregation Play Polysaccharides Proteins Publishing Recombinants Risk Role Signal Transduction Site Stroke Testing Thrombosis Thrombus United States antagonist artery occlusion atherosclerotic plaque rupture disability in vivo inhibitor injured insight interest podoplanin prevent receptor sialylation side effect targeted agent thrombotic von Willebrand Factor

项目摘要

PROJECT SUMMARY/ABSTRACT Arterial thrombotic diseases such as ischemic heart disease are the leading cause of disability and death in the United States. Platelet adhesion and formation of thrombotic platelet aggregates at the site of a ruptured atherosclerotic plaque or damaged endothelium under arterial blood flow is essential in the pathogenesis of arterial thrombosis. Under high or disturbed flow conditions, the initial interaction between platelets and the vessel wall is primarily mediated by von Willebrand factor (vWF) and platelet glycoprotein Iba (GPIba), which subsequently leads to platelet content release, aggregation, and activation of the coagulation. These mechanisms, which are critical for both hemostasis and thrombosis, are targets of current FDA-approved antiplatelet therapies. Although they are effective, all have the life-threatening side effect of causing bleeding, which significantly limits their clinical use. To address this unmet need, it is critical to further elucidate insights into mechanisms essential for thrombosis but dispensable for hemostasis. Recent published data from several independent labs show that platelet CLEC-2 (C-type lectin-like receptor 2) is important in arterial thrombosis. However, how CLEC-2 regulates arterial thrombosis is unknown. The lectin-domain of CLEC-2 is known to bind to sialylated O-glycans. Our preliminary data showed that CLEC-2 interacts with GPIba in a sialylation-dependent manner. Furthermore, our preliminary results reveal that CLEC-2 promotes GPIba- mediated activation of integrin αIIbβ3, which is critical for arterial thrombus growth and stability in vivo. Importantly, blocking CLEC-2 function does not prolong the bleeding time in vivo. Therefore, we hypothesize that CLEC-2 is critical for GPIba-mediated platelet activation that is required for arterial thrombus growth and stability. To test this, we will 1) test the hypothesis that CLEC-2 regulates GPIba-mediated platelet activation through interaction between its lectin-like domain and sialylated O-glycans of GPIba as GPIba is heavily modified by sialylated O-glycans; 2) determine if/how CLEC-2 stabilizes the arterial thrombus by facilitating GPIba-mediated integrin aIIbb3 activation using mouse and human arterial thrombosis models. CLEC-2 and GPIba are expressed at similar high levels on murine platelets, and both receptors are essential in arterial thrombosis. However, the mechanisms underlying their role in arterial thrombosis have been either elusive (GPIba) or unknown (CLEC-2). Our proposed study will provide new mechanistic insights into these outstanding questions in the field. It may lead to the development of a new effective and safe anti-thrombosis therapy.

项目摘要/摘要动脉血栓性疾病（例如缺血性心脏病）是残疾和死亡的主要原因美国。血小板粘附和在破裂部位的血栓形成血小板聚集体的形成动脉血流下的动脉粥样硬化斑块或损伤内皮在动脉的发病机理中至关重要血栓形成。在高或干扰的流动条件下，血小板与容器壁之间的初始相互作用为主要是由von Willebrand因子（VWF）和血小板糖蛋白IBA（GPIBA）介导的，随后导致到凝结的血小板含量释放，聚集和激活。这些机制，对于止血和血栓形成都是当前FDA批准的抗血小板疗法的靶标。虽然是有效，所有这些都具有危及生命的副作用，导致出血，这显着限制了其临床使用。到满足了这种未满足的需求，至关重要可用于止血。来自几个独立实验室的最近发布的数据表明，血小板CLEC-2（c型杆样接收器2）是在动脉血栓形成中很重要。但是，CLEC-2如何调节动脉血栓形成是未知的。讲座域已知CLEC-2与硫化的O-聚糖结合。我们的初步数据表明CLEC-2与GPIBA相互作用以靠苷的依赖性方式。此外，我们的初步结果表明，CLEC-2促进了GPIBA- 介导的整合素αIIBβ3的激活，这对于动脉血栓生长和体内稳定性至关重要。重要的是，阻止CLEC-2功能不会在体内延长出血时间。因此，我们假设CLEC-2是对于动脉血栓生长和稳定性所需的GPIBA介导的血小板激活至关重要。为了测试这一点，我们将1）检验CLEC-2的假设，即CLEC-2通过相互作用调节GPIBA介导的血小板激活它的gpiba的讲座状域和囊裂糖型O-glycans作为GPIBA，被囊化的O-Glycans大量修饰。 2）通过支持GPIBA介导的整联蛋白AIIBB3激活使用CLEC-2是否稳定动脉血栓是否稳定动脉血栓小鼠和人类动脉血栓形成模型。 CLEC-2和GPIBA在鼠血小板上以相似的高水平表达，并且两个受体在动脉血栓形成。但是，其在动脉血栓形成中作用的机制是难以捉摸的（GPIBA）或未知（CLEC-2）。我们提出的研究将为这些杰出的研究提供新的机械见解在现场的问题。它可能导致开发一种新的有效且安全的抗紧密疗法。