Characterizing cell adhesion and migration of surfaces biofunctionalized with nanopatterned collagen matrices

我们最近开发了一种在非生物表面创建超薄(~3 nm)胶原基质的方法，其中单个胶原微纤维在纳米尺度上几乎完全有序。初步实验表明，通过调节胶原基质的纳米形貌特征，可以精确控制不同细胞类型的黏附和迁移特性。这种纳米胶原蛋白基质作为智能可编程涂层用于表面生物功能化的未来需要对细胞对图案基质反应的分子机制有深刻的理解。含有整合素的黏附复合体，如焦点黏附，是细胞-基质黏附的主要媒介，将细胞骨架与细胞外基质联系起来。因此，为了了解我们的纳米基质的微纤维如何调节细胞的形态和迁移，阐明它们如何指导局部粘连的形成和调节细胞骨架的重排将是至关重要的。我们打算利用光学和原子力显微镜(AFM)相结合的方法在分子水平上研究纳米胶原蛋白晶格对焦点黏附形成和细胞骨架重排的影响。此外，胶原纳米拓扑学对整合素介导的黏附的影响将使用原子力显微镜单分子力谱进行定量。阐明细胞对胶原基质反应的分子机制不仅有助于提高其生物相容性，促进智能生物功能化材料的设计，而且还将为细胞识别和响应周围地形特征的机制提供新的见解。

We have recently developed a method for creating ultrathin (~ 3 nm) collagen matrices on non-biological surfaces in which individual collagen microfibrils are almost perfectly ordered on the nanoscale. Initial experiments show that by adjusting nanotopographic features of the collagen matrix, the adhesive and migratory properties of different cell types can be precisely controlled. The future use of such nanopatterned collagen matrices as intelligent, programmable coatings for the biofunctionalization of surfaces requires a profound understanding of the molecular mechanisms underlying the cellular response to the patterned matrix. Integrin-containing adhesion complexes, such as focal adhesions, are the main mediators of cell-substratum adhesion and link the cytoskeleton to the extracellular matrix. Consequently, for understanding how the microfibrils of our nanopatterned matrices regulate cell morphology and migration it will be crucial to elucidate how they direct the formation of focal adhesions and regulate cytoskeletal rearrangement. We intend to investigate the influence of nanopatterned collagen lattices on focal adhesion formation and cytoskeletal rearrangement at a molecular scale by employing a combination of light and atomic force microscopy (AFM) methods. Furthermore, the effect of the collagen nanotopography on integrin-mediated adhesion will be quantitated using AFM single molecule force spectroscopy. Elucidation of the molecular mechanisms underlying the cellular response to collagen matrices will not only help to improve their biocompatibility and facilitate the design of intelligent, biofunctionalized materials, but it will also offer new insight into the mechanisms by which cells recognize and respond to topographic features in their surrounding.