Nanostructure Devices for Measuring Cell Mechanics

用于测量细胞力学的纳米结构装置

• 批准号: 7025538
• 负责人: MICHAEL Patrick SHEETZ
• 金额: $ 27.27万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7025538
• 关键词: biomaterial development /preparation; biomaterial evaluation; biomaterial interface interaction; biophysics; cell adhesion; cell line; cell motility; cellular polarity; cytoskeletal proteins; extracellular matrix; fibronectins; integrins; membrane structure; molecular dynamics; nanotechnology; particle beam; surface property; technology /technique development

DESCRIPTION (provided by applicant): Cellular environment is a major factor in determining cell behavior and ultimately cell phenotype. Many recent studies have shown that the mechanical aspects of the environment are important factors in determining the cell response. The mechanical factors that appear critical are the nanometer level spacing, curvature, and rigidity of the extracellular matrix components. We have formed a collaboration between two nanofabrication labs and a cell biology lab to explore how these factors are sensed by cells at the molecular level. Using an e-beam writing system, we will be able to create cellular sized arrays with a range of nanometer level features that will enable us to screen for the critical distances and patterns that trigger cell responses. Once we define the critical distance for a cell response such as cell spreading, we will screen a number of cell lines that are missing critical motility and signaling proteins to determine if the cell spreading response is altered. Of particular interest is talin that has multiple integrin binding sites spaced over about 55 nm. In regard to membrane curvature, we have observed that cells respond to collagen and other fibers by extending lamellipodia with myosin II-B in them and myosin II-B-/- cells contract fibers at less than 30% efficiency. We will fabricate fibers and 2-D surface features with different radii of curvature and use the assembly of GFP-myosin II-B in lamellipodia as a criterion for defining the range of curvatures that elicit the response. Cells not only follow fibers but also follow surface features through contact guidance and we will explore the important parameters in determining cell polarization and tracking. Recent results indicate that specific mutations will dramatically affect the ability of cells to polarize and move, giving rise to grossly abnormal morphologies that will enable us to understand important cellular parameters involved in contact guidance. Rigidity sensing is critical for cell spreading and growth and we have defined a number of proteins that are needed to sense the difference between rigid and soft surfaces. The development a device for probing the effect of changes in surface rigidity on adjacent regions of the cell surface will enable us to probe the detailed mechanism of rigidity sensing. Knowing both the size and geometry of surface features that are sensed by the cells will enable us to elicit given cell behaviors in a defined way. Knowing the proteins involved will enable us to use targeted pharmacological inhibitors to alter morphology in defined ways. These studies have many practical applications in tissue engineering and in designing potential therapies for wound healing, cancer and a variety of disorders.

描述（由申请人提供）：细胞环境是决定细胞行为和最终细胞表型的主要因素。最近的许多研究表明，环境的机械方面是决定细胞反应的重要因素。出现关键的机械因素是细胞外基质组分的纳米级间距、曲率和刚度。我们已经在两个纳米纤维实验室和一个细胞生物学实验室之间建立了合作关系，以探索这些因子是如何在分子水平上被细胞感知的。使用电子束写入系统，我们将能够创建具有一系列纳米级特征的细胞大小的阵列，这将使我们能够筛选触发细胞反应的临界距离和模式。一旦我们定义了细胞反应的临界距离，例如细胞扩散，我们将筛选一些缺少关键运动和信号蛋白的细胞系，以确定细胞扩散反应是否改变。特别感兴趣的是具有间隔超过约55 nm的多个整联蛋白结合位点的talin。关于膜曲率，我们已经观察到，细胞响应胶原蛋白和其他纤维通过延长板状伪足与肌球蛋白II-B在他们和肌球蛋白II-B-/-细胞收缩纤维在小于30%的效率。我们将制造具有不同曲率半径的纤维和2-D表面特征，并使用GFP-肌球蛋白II-B在板状伪足中的组装作为定义引起响应的曲率范围的标准。细胞不仅遵循纤维，而且通过接触引导遵循表面特征，并且我们将探索确定细胞极化和跟踪的重要参数。最近的研究结果表明，特定的突变将极大地影响细胞的移动和移动能力，从而产生严重异常的形态，这将使我们能够了解接触指导中涉及的重要细胞参数。刚性感测对于细胞的扩散和生长至关重要，我们已经定义了一些蛋白质，这些蛋白质需要感测刚性和软表面之间的差异。开发一种用于探测细胞表面相邻区域表面刚度变化的影响的装置，将使我们能够探测刚度传感的详细机制。了解细胞所感知的表面特征的大小和几何形状将使我们能够以定义的方式引出给定的细胞行为。了解所涉及的蛋白质将使我们能够使用靶向药理学抑制剂以确定的方式改变形态。这些研究在组织工程和设计伤口愈合、癌症和各种疾病的潜在疗法方面有许多实际应用。