Nanostructure Devices for Measuring Cell Mechanics

细胞环境是决定细胞行为和最终细胞表型的主要因素。许多 最近的研究表明，环境的机械方面是影响 确定细胞的反应。看起来关键的机械因素是纳米级间距， 细胞外基质成分的曲率和刚性。我们已经在两家公司之间建立了合作关系 纳米制造实验室和细胞生物学实验室，以探索这些因素是如何被细胞在分子上感知的 水平。使用电子束写入系统，我们将能够创建细胞大小的阵列，其范围为 纳米级功能，使我们能够筛选触发细胞的关键距离和图案 回应。一旦我们定义了细胞反应的临界距离，例如细胞扩散，我们将筛选一个 缺少关键运动性和信号蛋白以确定细胞是否扩散的细胞系的数量 反应被改变了。特别令人感兴趣的是Talin，它具有多个整合素结合位点 55 nm。关于膜曲率，我们观察到细胞对胶原和其他纤维有反应。 通过延长含有肌球蛋白II-B的片状脂质体和肌球蛋白B-L-细胞收缩纤维不到30% 效率。我们将制作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在片状脂质体中的组装作为定义引起 回应。细胞不仅跟随纤维，而且通过接触引导跟随表面特征，我们将 探索决定细胞极化和追踪的重要参数。最近的结果表明， 特定的突变将极大地影响细胞极化和移动的能力，从而导致严重的 异常形态将使我们能够了解接触中涉及的重要细胞参数 指导。刚性感知对于细胞的扩散和生长至关重要，我们已经定义了一些 识别坚硬表面和柔软表面之间的差异所需的蛋白质。发展的时代 用于探测表面刚性变化对细胞表面相邻区域的影响的装置将使 我们将探索刚性传感的详细机制。了解曲面的大小和几何形状 由细胞感知的特征将使我们能够以一种定义的方式引出给定的细胞行为。知道 所涉及的蛋白质将使我们能够使用靶向药物抑制物来改变定义的 方式。这些研究在组织工程和设计潜力方面有许多实际应用。 治疗伤口愈合、癌症和各种疾病。

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 \\-B-l- 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.