Cell Anchoring on Nanopatterned Surface Functionality

描述（由申请人提供）：细胞附着和细胞间接触的建立是先进生物材料发展的关键问题之一。在外力作用下，许多影响细胞附着、运动和保持的参数已经确立。其中包括化学性质和特定功能和因子的呈现，以及细胞附着位点分布的几何方面（焦点接触）和细胞几何形状，这两者都会诱导细胞反应和表型变化。系统地研究纳米尺度的分布和焦点接触的大小以及微观细胞形状对细胞粘附稳定性的影响，将使用一种由自组装产生的通用的、无地形的纳米图案衬底。利用血管内皮细胞作为一种天然的二维细胞类型，对血管移植物的播种具有重要的临床意义，这种纳米图谱方法将阐明内皮细胞如何附着在表面，建立所需的表型，并通过形成明确和稳定的细胞-细胞接触来构建完整的血管内膜。推动这项工作的假设是，在生理剪切应力下，内皮细胞锚定的明确附着位点的纳米模式分布导致内皮细胞稳定。这一假设将通过(1)使用自组装方法设计和制造具有控制尺寸和生物功能的光滑纳米图案表面来验证；(2)将内皮细胞植入纳米图案上，并分析它们在静态和流动条件下的粘附性、细胞骨架排列、细胞间接触的发展和动态。(3)将(2)的结果与对微加工或成型工艺产生的地形纳米图案表面的观察和测量结果进行对比。这项研究将揭示内皮细胞分化和活性与下表面几何和化学性质之间的系统关系。该结果将提供新的设计原则，以增强传统聚合物或现代组织工程移植材料的播种过程，以建立能够长期预防血管闭塞的内皮细胞衬里。这样的原理可能会导致长期寻求的设计动脉，在其主要结构成分和内层中进行组织工程，并揭示细胞-生物材料相互作用的一般机制。

DESCRIPTION (provided by applicant): Cellular attachment and the establishing of cell-cell contacts is one of the key questions in the development of advanced biomaterials. Many parameters that influence cell attachment, motility, and retention under external forces have already been established. Among these are the chemical properties and the presentation of specific functionalities and factors, but also geometric aspects of the distribution of cellular attachment sites (focal contacts) and the cellular geometry, both of which induce cellular responses and changes in phenotype. A systematic investigation of the influence of the nanoscopic distribution and size of focal contacts and of the microscopic cell shape on the stability of cellular adhesion will use a versatile, topography-free nanopatterned substrate produced by self-assembly. Using vascular endothelial cells as a naturally two-dimensional cell type of great clinical significance for the seeding of vascular grafts, this nanopatterning approach will shed light on how endothelial cells attach to surfaces, establish the required phenotype, and build a complete vessel lining by forming well-defined and stable cell-cell contacts. The hypothesis driving this work is that a nanopatterned distribution of well-defined attachment sites for the anchoring of endothelial cells results in a stable endothelium under physiologic shear stress. This hypothesis will be tested by (1) designing and fabricating smooth nanopatterned surfaces of controlled size and biological functionality using self-assembly methods, (2) seeding endothelial cells onto nanopatterns and analyzing their adhesion, cytoskeletal arrangement, and intercellular contact development and dynamics under both static and flow conditions, (3) contrasting the results of (2) with observations and measurements on topographic nanopatterned surfaces created by micromachining or molding processes. This study will reveal systematic relationships between endothelial cell differentiation and activity and the geometric and chemical properties of the underlying surface. The results will provide new design principles to enhance the seeding processes for either traditional polymeric or modern tissue-engineered graft materials to establish an endothelial cell lining that is capable of long-term prevention of vascular occlusion. Such principles could lead to the long-sought designed arteries that are tissue-engineered in their main structural components as well as in the inner lining, and shed light in general on the mechanisms of cell-biomaterial interactions.