Mechanobiology of the Endothelial Cell Glyxcocalyx

在过去的15年里，我的实验室开发了独特的模型和技术来帮助理解细胞如何感知和响应机械力(机械生物学)。在接下来的5年里，我将使用我的NSERC发现基金来进一步研究内皮细胞机械生物学。最近的工作使我们将重点放在覆盖细胞的凝胶样层-糖萼(GCX)的作用上。这种以糖为基础的微妙结构被认为是内皮细胞生理的主要调节因素。我们已经证明，GCX的酶降解取消了这些细胞对壁切应力的自然反应。我们还观察到，壁切应力梯度区域的内皮细胞显示出对GCX的损伤。我们假设，对内皮细胞GCX的损伤可以破坏细胞的自然机械生物学，导致功能障碍。细胞如何将机械压力转化为生物事件(机械转导)还知之甚少。此外，细胞如何调节感知这些压力的元件(机械传感器)在很大程度上还没有被发现。这项拟议研究的长期目标是了解参与机械转导的细胞信号，以及细胞如何通过操纵其机械传感器来调节这种反应。在接下来的5年里，我的实验室将专注于GCX的机械生物学。具体地说，我们将使用我们的体外模型： 1.了解细胞如何在生物机械力的作用下调节其糖基化反应 2.确定对机械传感重要的糖萼组分 3.阐明与糖萼机械转导相关的信号通路 这项研究将包括旨在将定义的壁切应力梯度传递给体外培养的内皮细胞的实验。力学环境对GCX脱落和再生长的影响将被识别。我们还将操纵内皮细胞GCX的组成，以确定关键成分和减轻损害的方法。我们将阻止GCX参与机械转导的可疑通路，以解开细胞内信号转导。 总体而言，这项工作将进一步加深我们对细胞中允许它们适应机械环境的基本过程的理解。所获得的基础数据将对组织工程、药物发现、发育生物学和病理学产生重大影响。该项目将为HQP提供良好的培训环境。它将通过开发新的模型和分析技术来推动科学和工程的边界。最后，这项工作将要求HQP在多学科环境中工作，利用他们的工程背景来阐明GCX的机械生物学。

Over the past 15 years, my lab has developed unique models and techniques to help understand how cells sense and respond to mechanical forces (mechanobiology). In the next 5 years I will use my NSERC discovery grant to further our investigation into endothelial cell mechanobiology. Recent work has led us to focus on the role of the gel-like layer that covers cells, the glycocalyx (GCX). This delicate sugar-based structure is believed to be a major regulator of endothelial cell physiology. We have shown that enzymatic degradation of the GCX abrogates the natural response of these cells to wall shear stress. We have also observed that endothelial cells in regions of wall shear stress gradients show damage to the GCX. We hypothesize that damage to the endothelial cell GCX can unbalance the natural mechanobiology of cells leading to dysfunction. How cells convert mechanical stress into biological events (mechanotransduction) is poorly understood. Moreover, how the cell regulates the elements that sense these stresses (mechanosensors) is largely undiscovered. The long term goal of the proposed research is to understand the cellular signaling involved in mechanotransduction and how the cell regulates this response by manipulating its mechanosensors. In the next 5 years, my lab will focus on the mechanobiology of the GCX. Specifically, we will use our in vitro models to: 1. Understand how cells regulate their glycocalyx in response to biomechanical forces 2. Identify components of the glycocalyx important to mechanosensing 3. Elucidate signaling pathways linked to glycocalyx mechanotransduction The research will include experiments designed to impart defined wall shear stress gradients to endothelial cells in vitro. The effect of the mechanical environment on shedding and regrowth of the GCX will be identified. We will also manipulate the composition of the endothelial cell GCX to identify key components and ways to mitigate damage. We will block suspected pathways involved in mechanotransduction by the GCX to unravel intracellular signaling. Overall, the work will further our understanding of the fundamental process in cells that allow them to adapt to their mechanical environment. The underlying data obtained will have a significant impact in tissue engineering, drug discovery, developmental biology and pathology. The program will provide an excellent training environment for HQP. It will push the boundaries of science and engineering by developing new models and analysis techniques. Finally, the work will require HQP to work in a multidisciplinary environment, leveraging their engineering background to elucidate the mechanobiology of the GCX.