SYNDECAN-4 IN VASCULAR SMOOTH MUSCLE CELL MIGRATION

描述（改编自申请人的摘要）：间充质细胞 迁移与矩阵生产和重组 分泌的纤维蛋白网络，都有助于区域组织 重塑与潜在的病变形成的血管壁。 的 在这个建议中的实验方法旨在产生基本的 关于细胞表面硫酸肝素蛋白聚糖、多配体蛋白聚糖 4，其是调节细胞迁移的重要分子决定子， 基质重塑 具体而言，研究人员打算：1）定义 syndecan 4在调节血管平滑肌细胞迁移中作用 速度和方向持久性。 这一系列的实验将定义 多配体蛋白聚糖4调节细胞速度，定向持久性， 以及细胞在存在和不存在的情况下向运动表型的定型， 不存在硫酸肝素结合化学引诱物。 特别是运动性 将使用延时荧光视频显微镜分析行为 与计算技术和数学公式有关。 2)表征多配体蛋白聚糖4影响整合素依赖性细胞凋亡的能力。 细胞/基质粘附行为。 的动力学和强度 将在确定的细胞系中研究细胞-底物结合强度 并利用差速离心测定法在模型基底上进行。 这些生物物理学研究将与时间相关 细胞形态和基质的免疫荧光显微镜研究 重组。 这些调查将使我们了解 多配体蛋白聚糖4如何通过其对细胞底物作用影响运动性 粘连 3)确定syndecan 4在控制细胞牵引中的作用 力和血管平滑肌细胞介导的基质重塑。 的 细胞牵引力的产生和基质重塑将在 纤维蛋白和胶原微球填充变异细胞系。 数学模型将用于表征细胞牵引力的变化， 实验系统中扰动的函数。 使用这些 分析工具，牵引介导的影响将进行调查 与重塑中的其他潜在重要变量无关 过程，如细胞生长、基质机械性能和组织 几何

DESCRIPTION (Adapted from the Applicant's Abstract): Mesenchymal cell migration in association with matrix production and the reorganization of secreted fibrillar protein networks, all contribute to regional tissue remodeling with the potential of lesion formation in the vascular wall. The experimental approach in this proposal is designed to yield fundamental knowledge regarding the cell surface heparin sulfate proteoglycan, syndecan 4, which is an important molecular determinant modulating cell migration and matrix remodeling. Specifically, the investigators intend to: 1) Define the role of syndecan 4 in modulating vascular smooth muscle cell migration speed and directional persistence. This series of experiments will define the ability of syndecan 4 to modulate cell speed, directional persistence, and the commitment of cells to a motile phenotype in both the presence and absence of heparin sulfate binding chemoattractants. Specifically, motility behavior will be analyzed using time-lapse epifluorescence videomicroscopy in association with computational techniques and mathematical formulations. 2) Characterize the ability of syndecan 4 to influence integrin dependent cell/substrate adhesive behavior. The kinetics and magnitude of cell-substrate binding strength will be investigated in defined cell lines and on model substrates utilizing a differential centrifugation assay. These biophysical studies will be correlated with time-dependent immunofluorescence microscopy studies of cell morphology and matrix reorganization. Together these investigations will allow us to understand how syndecan 4 can influence motility by its effect on cell-substrate adhesion. 3) Identify the role of syndecan 4 in governing cell traction forces and vascular smooth muscle cell mediated matrix remodeling. The generation of cell traction forces and matrix remodeling will be studied in fibrin and collagen microspheres populated with variant cell lines. Mathematical models will be used to characterize changes in cell traction as a function of perturbations in the experimental system. Using these analytical tools, traction mediated effects will be investigated independently of other potentially important variables in the remodeling process, such as cell growth, matrix mechanical properties, and tissue geometry.