Deciphering the Molecular Dynamics of Cell Adhesion and the Role of Biomechanics in Ehlers-Danlos Syndrome

细胞与其环境形成的连接是生物体最基本的过程之一，异常的连接导致病理条件的发展。整合素通过形成对组织完整性至关重要的粘附位点来介导这些与周围细胞外基质（ECM）的连接。根据病理条件，整合素亚型的表达水平发生变化，这可能发生在结缔组织疾病Ehlers-Danlos综合征（EDS）中。EDS细胞显示纤连蛋白受体整联蛋白的表达减少，随之而来的是替代受体整联蛋白的募集。然而，还假设这些粘附位点的分子组成也设定它们的强度和稳定性，最终影响肌动蛋白细胞骨架和细胞的生物力学性质，这在EDS中尚未研究。这些粘附位点形成的机械化学细节也仍然知之甚少。我们建议使用一种新开发的检测方法，该方法采用功能化弹性体来模拟ECM，从而控制细胞培养的机械和生物化学环境。这允许研究粘附蛋白类型和混合物在粘附位点形成中的作用。弹性体与单轴细胞拉伸器的组合还允许在细胞粘附期间施加应力。活细胞显微镜结合图像分析工具来量化成像数据，将为细胞粘附的动力学提供更深入的见解。通过这一点，我们试图了解如何改变整合素的配置文件可以影响细胞的机械性能，如何粘附网站和肌动球蛋白动力学改变响应机械刺激，如果这是在EDS的影响。该项目的结果将提供重大进展，在我们的理解过程中涉及保持组织完整性的条件下，如EDS。

The connections a cell forms with its environment underlies one of the most fundamental processes of organisms, with aberrant connections leading to the development of pathological conditions. Integrins are essential for mediating these connections to the surrounding Extracellular Matrix (ECM) through formation of adhesion sites which are crucial for tissue integrity. Depending on pathological condition, the expression level of integrin isoforms change, which may be occurring in the connective tissue disorder Ehlers-Danlos Syndrome (EDS). EDS cells display a reduced expression of the fibronectin receptor integrin with the consequent recruitment of the alternative receptor integrin. However, it is also assumed the molecular composition of these adhesion sites also sets their strength and stability, ultimately influencing the actin cytoskeleton and a cell's biomechanical properties which has not been studied in EDS. The mechanochemical details of the formation of these adhesion sites also remain poorly understood. We propose using a newly developed assay that employs functionalised elastomers to mimic the ECM, allowing control of the mechanical and biochemical environment into which cells are cultured. This allows to study the role of adhesion protein type and mixture in adhesion site formation. Combination of the elastomer to a uniaxial cell-stretcher also allows for stresses to be applied during cell adhesion. Live cell microscopy combined with image analysis tools to quantify imaging data will then provide deeper insights into the dynamics of cell adhesion. Through this, we seek to understand how an altered integrin profile can affect the mechanical properties of the cell, how adhesion site and actomyosin dynamics change in response to mechanical stimuli, and if this is affected in EDS. The results of this project will provide major advances in our understanding of the processes involved in maintaining tissue integrity in conditions like EDS.