Mechanical properties of VWF in single molecule and cell adhesion force experiments using AFM

使用 AFM 进行单分子和细胞粘附力实验中 VWF 的机械特性

• 批准号: 200682754
• 负责人: Dr. Martin Benoit
• 金额: --
• 依托单位: Institut für Biophysik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/200682754?language=en
• 关键词: Mechanical; properties; VWF; single; molecule

VWF is known to be a shear force sensitive molecule and designed to perform his encoded functions by conformational changes according to the actual shear situation in the blood stream. Even though extensive studies on blood platelet aggregation under shear flow and biochemical approaches elucidated the importance of these conformational changes of VWF for platelet adhesion, direct experimental investigations on the detailed mechanism and its dynamics are largely missing. In fact, there is a need of biophysical investigations of VWF for (i) the mechano-elastic characterization (e.g. load-extension response, relaxation times etc.), and (ii) the molecular recognition properties with respect to adhesion strength and localization of adhesion sites (e.g. endothelial cells, platelets etc.). Since interactions between VWF and collagen are a key initial step of hemostasis, VWF/collagen binding studies should be performed. Utilizing atomic force microscopy (AFM) the forces and dynamics of specific VWF-domain/collagen interactions on the single molecular level can directly be probed. As two specialized subgroups in Linz and Munich, we specifically focus our AFM expertise on the various interactions of VWF with cells and tissue components.In the first funding period we applied AFM as a new approach to probe the platelet adhesion to VWF, the size distribution of VWF, the unfolding of VWF-dimers, and the dynamics of binding of selected VWF domains to other VWF domains and to collagen III and VI. For the second funding period we will gain a detailed understanding of the biophysical functionalities of the VWF protein on the single domain level by establishing a unique combination of nano-mechanics and computer simulation studies with Netz (B4), and Gräter/Baldauf (C1). According to the main task, exploring the links between the mechanical properties of the mechano-sensitive VWF molecule and its function in the interplay with blood components, we will study the formation of VWF-platelet networks and the impact of pathologic VWF mutations in close collaboration with groups Schneppenheim (A1), Wilmanns (C3) Schneider (A2), Wixforth (B1), Rädler (B3). We will thus extend our investigations to collagen type I and IV, to integrin mediated adhesion of VWF to platelets, and to endothelial cells under inflammatory conditions. Furthermore, we will directly measure changes in the force signature by stretching VWF and VWF mutants under inflammatory conditions. We expect that the clinical relevance of our findings will aid to detect disease and improve the treatment of VWF patients.

众所周知，VWF是一种剪切力敏感的分子，它的设计是根据血流中的实际剪切力情况，通过构象变化来执行其编码功能。尽管剪切流和生化方法下对血小板聚集的广泛研究阐明了这些VWF构象变化对血小板黏附的重要性，但对其详细机制及其动力学的直接实验研究还很少。事实上，需要对VWF进行生物物理研究：(1)机械弹性特性(如载荷-延伸响应、松弛时间等)；(2)与黏附强度和黏附部位(如内皮细胞、血小板等)定位有关的分子识别特性。由于VWF和胶原之间的相互作用是止血的关键初始步骤，因此应该进行VWF/胶原结合的研究。利用原子力显微镜(AFM)可以直接在单分子水平上探测特定的VWF结构域/胶原蛋白相互作用的力和动力学。作为林茨和慕尼黑的两个专门小组，我们特别专注于VWF与细胞和组织组件的各种相互作用。在第一个资助期，我们应用AFM作为一种新的方法来探测VWF与血小板的黏附、VWF的尺寸分布、VWF二聚体的展开，以及选定的VWF结构域与其他VWF结构域以及与III和VI胶原结合的动力学。在第二个资助期，我们将通过与Netz(B4)和Gräter/Baldauf(C1)建立独特的纳米力学和计算机模拟研究相结合的方式，在单个结构域水平上详细了解VWF蛋白质的生物物理功能。根据主要任务，探索机械敏感的VWF分子的机械性能与其与血液成分相互作用中的功能之间的联系，我们将与Schneppenheim(A1)、Wilmanns(C3)Schneider(A2)、Wixforth(B1)、Rädler(B3)小组密切合作，研究VWF-血小板网络的形成和病理性VWF突变的影响。因此，我们将把我们的研究扩展到I型和IV型胶原，整合素介导的VWF与血小板的黏附，以及炎症条件下的内皮细胞。此外，我们将通过在炎症条件下拉伸VWF和VWF突变体来直接测量力信号的变化。我们期望我们的发现的临床相关性将有助于发现疾病和改善VWF患者的治疗。

项目成果

Interaction of von Willebrand factor domains with collagen investigated by single molecule force spectroscopy.

通过单分子力谱研究冯维勒布兰德因子域与胶原蛋白的相互作用

• DOI: 10.1063/1.5007313
• 发表时间: 2018
• 期刊: The Journal of chemical physics
• 作者: Posch S;Obser T;König G;Schneppenheim R;Tampé R;Hinterdorfer P
• 通讯作者: Hinterdorfer P

VWF - Collagen Interactions Studied with Single Molecule Force Spectroscopy

VWF - 用单分子力谱研究胶原蛋白相互作用

• DOI: 10.1016/j.bpj.2013.11.2551
• 发表时间: 2014
• 期刊: Biophysical Journal
• 影响因子: 3.4
• 作者: Posch S;Obser T;Brehm AM;Gruber HJ;Schneppenheim R;Tampé R;Hinterdorfer P
• 通讯作者: Hinterdorfer P

Mechanosensitive Von Willebrand Factor Protein-Protein Interactions Regulate Hemostasis

机械敏感冯维勒布兰德因子蛋白质-蛋白质相互作用调节止血

• DOI: 10.1016/j.bpj.2014.11.2764
• 发表时间: 2015
• 期刊: Biophysical Journal
• 影响因子: 3.4
• 作者: Aponte-Santamaría C;Huck V;Posch S;Bronowska AK;Grässle S;Brehm AM;Obser T;Schneppenheim R;Hinterdorfer P;Schneider SW;Baldauf C;Gräter F
• 通讯作者: Gräter F