The surface property of biomaterials has a profound influence on the adhesion and biofunction of mesenchymal stem cells, which is vital for successful implantation and regeneration. Nanotopological surface is capable of mimicking bone's extracellular matrix (ECM) to regulate cell behavior, the understanding of which however remains elusive. In this study, we decoupled the effect of nanotopological cues from two perspectives: nanostructure and specific surface area. Bone marrow-derived mesenchymal stem cells (BMSCs) displayed stable and organized F-actin fibers, forming intricate myosin networks on the poly (ε-caprolactone) (PCL) substrate decorated with a well-defined nanopattern that was formed by the PCL lamellae. The cell spreading and myosin activation were limited when the specific surface area of the nanopattern was reduced. These findings illustrate that the specific surface area of the nanopatterned surface is a dominant regulator for cell mechanosensing. Our results highlight the potential of optimizing biomaterial interfaces to enhance cell adhesion and functionality for bone regeneration.

中文翻译：

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表面纳米图案促进骨髓基质细胞粘附和成骨的见解

生物材料的表面特性对间充质干细胞的粘附和生物功能有着深远的影响，这对于间充质干细胞的成功植入和再生至关重要。纳米拓扑表面能够模仿骨骼的细胞外基质（ECM）来调节细胞行为，但对此的理解仍然难以捉摸。在这项研究中，我们从两个角度解耦了纳米拓扑线索的影响：纳米结构和比表面积。骨髓间充质干细胞 (BMSC) 表现出稳定且有组织的 F-肌动蛋白纤维，在聚 (ε-己内酯) (PCL) 基底上形成复杂的肌球蛋白网络，基底上装饰有由 PCL 片层形成的明确纳米图案。当纳米图案的比表面积减小时，细胞扩散和肌球蛋白激活受到限制。这些发现表明，纳米图案表面的比表面积是细胞机械传感的主要调节剂。我们的结果凸显了优化生物材料界面以增强细胞粘附和骨再生功能的潜力。