Mechanoregulatory mechanisms of von Willebrand disease and thrombosis

血管性血友病和血栓形成的机械调节机制

• 批准号: 9386220
• 负责人: Hongxia Fu
• 金额: $ 17.81万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9386220
• 关键词: Adhesions; Affect; Affinity; Air Pressure; Area; Binding; Binding Sites; Biochemical; Biological Assay; Biomedical Engineering; Blood; Blood Circulation; Blood Coagulation Disorders; Blood Platelets; Blood Vessels; Blood coagulation; Blood flow; Cell model; Cells; Cellular biology; Complement; Complex; Diagnostic; Disease; Disease model; Elongation Factor; Endothelial Cells; Fluorescence; Fluorescence Microscopy; Foundations; Glycoproteins; Hemostatic function; Human; Human Cell Line; Individual; Inherited; Ionic Strengths; Laboratories; Length; Ligand Binding; Link; Membrane; Mentors; Mentorship; Methods; Microfluidics; Modeling; Molecular Conformation; Monitor; Mutation; Patients; Physiological; Platelet Glycoproteins; Play; Polymers; Population; Positioning Attribute; Process; Property; Recruitment Activity; Regulation; Reporter; Research; Research Personnel; Resolution; Role; Science; Shapes; Stem cells; Surface; System; Tertiary Protein Structure; Testing; Therapeutic; Thrombosis; Time; Training; Urea; Variant; Weibel-Palade Bodies; Work; base; body sense; career development; conformational conversion; extracellular; gain of function; genome editing; hydrodynamic flow; improved; in vivo; innovation; insight; interdisciplinary approach; molecular imaging; mutant; novel; novel strategies; physiologic model; prevent; programs; receptor; sensor; single molecule; solute; von Willebrand Disease; von Willebrand Factor

PROJECT SUMMARY A critical initiating step in hemostasis and thrombosis is adhesion of platelet membrane receptor glycoprotein Ibα (GPIbα) to von Willebrand factor (VWF), a large, multidomain, polymeric blood glycoprotein. The precise mechanisms whereby VWF promotes platelet GPIbα adhesion to its A1 domain only during hemostasis or thrombosis, but not in normal circulation, are not yet clear. Understanding these mechanisms is essential for developing more effective diagnostics and therapeutics for vascular thrombosis and the most common hereditary bleeding disorder, von Willebrand disease (VWD). The applicant, Dr. Hongxia Fu, will develop innovative single-molecule approaches to study full-length VWF concatemers hemostatic function in the laboratory of the mentor, Dr. Timothy Springer. This system can be utilized to monitor both intramolecular VWF conformational transitions and GPIbα binding simultaneously by combining rapid air pressure-actuated shear flow with total internal fluorescence microscopy (TIRF). Utilizing this system, Dr. Fu will test the hypothesis that hydrodynamic flow directly induces a conformational transition in VWF concatemers from a compact to an elongated form, thereby exposing high-affinity, force- dependent binding sites to recruit both GPIbα (platelet adhesion) and additional VWF molecules (VWF self- association). To expand this system to include complex features of physiological and pathophysiological blood flow, she will furthermore develop a new fluorescence-based assay for VWF function in bulk solutions and its expression in Weibel-Palade bodies inside endothelial cells with or without VWD-relevant mutations. This work will provide direct insight into the regulatory mechanisms governing primary hemostasis, thrombosis, and bleeding disorder, establishing a paradigm for mechanosensory control of receptor-ligand binding affinity. It also will provide Dr. Fu with additional training in cell biology, genome editing, stem cells, and biomedicine, complementing her expertise in quantitative sciences. Dr. Fu will devote 100 % of her time to research under the direct mentorship of Dr. Springer. Dr. Fu's research program will establish new quantitative assays for VWF function and VWF-related diseases, from the single molecule to the cellular scale, providing a firm foundation for continued research in this area and career development to the independent investigator stage in biomedicine.

项目总结