The nanopore size and roughness of nanoporous surface are two critical variables in determining stem cell fate, but little is known about the contribution from each cue individually. To address this gap, we use two-dimensional nanoporous membranes with controlled nanopore size and roughness to culture bone marrow-derived mesenchymal stem cells (BMSCs), and study their behaviors such as attachment, spreading and differentiation. We find that increasing the roughness of nanoporous surface has no noticeable effect on cell attachment, and only slightly decreases cell spreading areas and inhibits osteogenic differentiation. However, BMSCs cultured on membranes with larger nanopores have significantly fewer attached cells and larger spreading areas. Moreover, these cells cultured on larger nanopores undergo enhanced osteogenic differentiation by expressing more alkaline phosphatase, osteocalcin, osteopontin, and secreting more collagen type I. These results suggest that although both nanopore size and roughness can affect BMSCs, nanopore size plays a more significant role than roughness in controlling BMSC behavior.

中文翻译：

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解耦纳米孔大小和表面粗糙度对骨髓干细胞的附着，扩散和分化的影响。

纳米孔表面的纳米孔大小和粗糙度是决定干细胞命运的两个关键变量，但对于每种线索的贡献知之甚少。为了解决这个空白，我们使用具有受控纳米孔尺寸和粗糙度的二维纳米多孔膜来培养骨髓源性间充质干细胞（BMSC），并研究其行为，如附着，扩散和分化。我们发现增加纳米孔表面的粗糙度对细胞附着没有明显的影响，并且仅略微减少了细胞的扩散面积并抑制了成骨细胞的分化。但是，在具有较大纳米孔的膜上培养的骨髓间充质干细胞附着细胞明显较少，散布面积较大。此外，