Regulation of von Willebrand Factor - platelet binding by Force and Interdomain I

通过力和域间 I 调节血管性血友病因子 - 血小板结合

• 批准号: 8024519
• 负责人: Wendy E Thomas
• 金额: $ 44.55万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-12-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8024519
• 关键词: Adhesions; Adhesives; Adverse effects; Antibodies; Behavior; Binding; Biological Assay; Blood Platelets; Blood Vessels; Cardiovascular Diseases; Cause of Death; Cells; Cloning; Disease; Elements; Event; Exposure to; Glycoprotein Ib; Hemorrhage; Hemostatic function; Knowledge; Lead; Measures; Mechanics; Mediating; Microfluidics; Mutation; Myocardial Infarction; Nucleic Acid Regulatory Sequences; Physiological; Physiology; Plasma Proteins; Platelet aggregation; Point Mutation; Process; Protein Engineering; Recombinants; Regulation; Research Proposals; Role; Scanning Probe Microscopes; Site; Spectrum Analysis; Stress; Stretching; Stroke; Surface; System; Testing; Therapeutic Agents; Thrombosis; Thrombus; Work; base; fluid flow; in vivo; novel; prevent; receptor; research study; shear stress; single molecule; theories; von Willebrand Disease; von Willebrand Factor

DESCRIPTION (provided by applicant): Arterial thrombosis occurs in conditions of high fluid flow and is mediated by the binding of platelets via their receptor Glycoprotein Ib (GPIb) to the plasma protein called von Willebrand Factor (VWF) via the A1 domain. This process is normally down-regulated to prevent spontaneous adhesion and thrombosis, but is activated by high shear stress. The proposed work will test the hypothesis that binding of GPIb to A1 is down-regulated by the neighboring domains or flanking regions within VWF, so that VWF displays interdomain auto-inhibition. It will also test the hypothesis that mechanical force associated with high shear stress activates platelet binding by pulling these regulatory regions away from the A1 domain to relieve the auto- inhibition. The final hypothesis to be tested is that conditions that increase the spontaneous binding of platelets to VWF, including type 2B von Willebrand disease, do so by damaging the normal interdomain auto-inhibition. Regulatory domains and elements within VWF will be identified by cloning different regions of VWF and determining the adhesive behavior of both soluble and surface-immoblized molecules. The effect of mechanical force and shear stress on this regulation will be determined using an atomic force microscope and microfluidics after immobilizing the molecules in an oriented fashion. PUBLIC HEALTH RELEVANCE: Thrombosis prevents bleeding at the site of damaged blood vessels but can also lead to heart attacks or strokes, the leading causes of death in cardiovascular disease. Current treatments for cardiovascular disease often cause excessive bleeding, while treatments for bleeding disorders can cause thrombotic disorders. To develop new therapies without these fundamental trade- offs, we need to better understand how the thrombotic process is regulated in the body.

描述（由申请人提供）：动脉血栓形成发生在高流量条件下，由血小板通过其受体糖蛋白Ib（GPIb）与血浆蛋白（称为血管性血友病因子（VWF））通过A1结构域结合介导。该过程通常被下调以防止自发性粘连和血栓形成，但被高剪切应力激活。这项工作将验证GPIb与A1的结合受到VWF内邻近结构域或侧翼区域的下调，因此VWF显示结构域间自抑制的假设。它还将测试与高剪切应力相关的机械力通过将这些调节区域从A1结构域拉离以缓解自抑制来激活血小板结合的假设。最后要检验的假设是，增加血小板与VWF自发结合的条件，包括2B型血管性血友病，通过破坏正常的结构域间自身抑制来实现。通过克隆VWF的不同区域并确定可溶性和表面固定化分子的粘附行为，将鉴定VWF内的调节结构域和元件。在以定向方式固定分子后，将使用原子力显微镜和微流体来确定机械力和剪切应力对该调节的影响。 公共卫生关系：血栓形成可以防止受损血管部位出血，但也可能导致心脏病发作或中风，这是心血管疾病死亡的主要原因。目前对心血管疾病的治疗经常导致过度出血，而对出血性疾病的治疗可能导致血栓性疾病。为了开发没有这些基本权衡的新疗法，我们需要更好地了解血栓形成过程在体内是如何调节的。