Biomaterials Directed Cell Polarity and Migration

描述(由申请人提供)：细胞运动性在组织形态发生、胚胎发育、血管生成和伤口愈合中起着核心作用。在体外诱导定向细胞迁移、自下而上组装组织模式、伤口愈合和芯片上细胞装置的主要技术依赖于外部梯度和趋化作用。然而，由于细胞对梯度的反应范围有限，引导大量细胞群体独立地远距离迁移仍然是一个挑战。在过去的资助期间，我们报告了引导细胞迁移的创新技术，使用：2D表面微图案(Mandip-微阵列自然定向持续放大)和3D微通道(TANDIP-自然定向持续地形放大)。没有渐变，ManDIP和TANDIP具有高度的可扩展性，可以并行操作，在复杂路径上引导无限距离的大量单元。这种能力的示范应用包括人工诱导的不同细胞群体在空间上的自组装 通过细胞的内在运动性来定义细胞的结构和分类。使用ManDIP、TANDIP和一种制造具有光切换细胞粘附性的底物的新技术，我们现在可以从机械上探索细胞如何感知周围的细胞外基质(ECM)来极化和定向迁移，无论是沿着或反对其初始形态极化。我们也 与加州大学医学院和儿童医院的4名合作者合作，他们专门研究迁移、信号通路和细胞极性。在第一次竞争性更新应用中，我们将通过解决以下具体问题来重点了解细胞极化和迁移过程中发生的关键事件的顺序和相互依赖关系：目的1.片状脂虫附着的局部变化如何改变形态极化？目的2.几何细胞-底物相互作用如何引导高尔基体极化？目的3.不同类型的细胞对生物力学提示的反应有何不同？

DESCRIPTION (provided by applicant): Cell motility plays a central role in tissue morphogenesis, embryonic development, angiogenesis, and wound healing. The primary techniques for inducing directional cell migration in vitro, for bottom-up assembly of tissue patterns, wound healing, and cell- on-chip devices, rely on external gradients, chemotaxis. However, due to the finite range of gradients that cells respond to, steering the migration of large population of cells independently over long distances remains a challenge. Over the past funding period, we reported innovative techniques for guiding cell migration using: 2D surface micropatterns (MANDIP - Microarray Amplification of Natural Directional Persistence) and 3D microchannels (TANDIP - Topographical Amplification of Natural Directional Persistence). Free from gradients, MANDIP and TANDIP are highly scalable and can operate in parallel to direct large number of cells over unlimited distances on complex paths. Demonstrated applications of this capability include MANDIP directed self- assembly of different cell populations into spatially defined structures and sorting of cells by their intrinsic motility. Using MANDIP, TANDIP, and a new technique for fabricating substrates with light-switchable cell adhesiveness, we can now probe mechanistically how cells sense their surrounding extracellular matrix (ECM) to polarize and migrate directionally either along or against their initial morphological polarization. We also partnered with 4 collaborators at UC Medical School and Childrens Hospital who specialize in migration signaling pathways and cell polarity. In this first competitive renewal application, we will focus on understanding the sequence and interdependency of key events that occur during cell polarization and migration by addressing the following specific questions: Aim 1. How do local changes in attachment of lamellipodia alter morphological polarization? Aim 2. How do geometric cell-substrate interactions direct Golgi polarization? Aim 3. How do different cell types differ in their response to biomechanical cues?