Limitations associated with current bone grafting materials has necessitated the development of synthetic scaffolds that mimic the native tissue for bone repair. Scaffold parameters such as pore size, pore interconnectivity, fibre diameter, and fibre stiffness are crucial parameters of fibrous bone tissue engineering (BTE) scaffolds required to replicate the native environment. Optimum values vary with material, fabrication method and cell type. Melt electrowriting (MEW) provides precise control over extracellular matrix (ECM)-like fibrous scaffold architecture. The goal of this study was to fabricate and characterise poly-ε-caprolactone (PCL) fibrous scaffolds with 100, 200, and 300 μm pore sizes using MEW and determine the influence of pore size on human bone marrow stem cell (hMSC) adhesion, morphology, proliferation, mechanosignalling and osteogenesis. Each scaffold was fabricated with a fibre diameter of 4.01 ± 0.06 μm. The findings from this study highlight the enhanced osteogenic effects of controlled micro-scale fibre deposition using MEW, where the benefits of 100 μm square pores in comparison with larger pore sizes are illustrated, a pore size traditionally reported as a lower limit for osteogenesis. This suggests a lower pore size is optimal when hMSCs are seeded in a 3D ECM-like fibrous structure, with the 100 μm pore size optimal as it demonstrates the highest global stiffness, local fibre stiffness, highest seeding efficiency, maintains a spread cellular morphology, and significantly enhances hMSC collagen and mineral deposition. Similarly, this platform represents an effective in vitro model for the study of hMSC behaviour to determine the significant osteogenic benefits of controlling ECM-like fibrous BTE scaffold pore size using MEW.

中文翻译：

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使用熔体电泳法制备的纤维支架内孔尺寸对人骨髓干细胞成骨作用的影响。

与当前的骨移植材料相关的局限性使得必须开发模仿天然组织以进行骨修复的合成支架。支架参数（例如孔径，孔互连，纤维直径和纤维刚度）是复制原始环境所需的纤维骨组织工程（BTE）支架的关键参数。最佳值随材料，制造方法和电池类型的不同而不同。熔融电子书写（MEW）提供对细胞外基质（ECM）样纤维支架结构的精确控制。这项研究的目的是使用MEW制备和表征孔径分别为100、200和300μm的聚ε-己内酯（PCL）纤维支架，并确定孔径对人骨髓干细胞（hMSC）黏附的影响，形态，增殖，机械信号传递和成骨。每个支架的纤维直径为4.01±0.06μm。这项研究的发现凸显了使用MEW进行可控的微尺度纤维沉积所产生的成骨作用，其中显示了100μm方形孔与较大孔径相比的优势，传统上孔径被报告为成骨作用的下限。这表明，当将hMSC植入3D ECM样的纤维结构中时，较低的孔径是最佳的，而100μm的孔径则最佳，因为它表现出最高的整体刚度，局部纤维刚度，最高播种效率，保持了散布的细胞形态，并显着增强hMSC胶原蛋白和矿物质沉积。同样，