i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal. INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Portugal. FEUP-Faculdade de Engenharia da Universidade do Porto, Departamento de Engenharia Metalúrgica e de Materiais, Portugal. MIRA-Institute for Biomedical Technology and Technical Medicine, Department of Tissue Regeneration, University of Twente, The Netherlands. MERLN-Institute for Technology Inspired Regenerative Medicine, Department of Complex Tissue Regeneration, Maastricht University, The Netherlands.
Biofabrication. 2016 May 24;8(2):025012. doi: 10.1088/1758-5090/8/2/025012.
Additive manufactured three-dimensional (3D) scaffolds with tailored surface topography constitute a clear advantage in tissue regeneration strategies to steer cell behavior. 3D fibrous scaffolds of poly(ethylene oxide terephthalate)/poly(butylene terephthalate) block copolymer presenting different fiber surface features were successfully fabricated by additive manufacturing combined with wet-spinning, in a single step, without any post-processing. The optimization of the processing parameters, mainly driven by different solvent/non-solvent combinations, led to four distinct scaffold types, with average surface roughness values ranging from 0.071 ± 0.012 μm to 1.950 ± 0.553 μm, average pore sizes in the x- and y-axis between 351.1 ± 33.6 μm and 396.1 ± 32.3 μm, in the z-axis between 36.5 ± 5.3 μm and 70.7 ± 8.8 μm, average fiber diameters between 69.4 ± 6.1 μm and 99.0 ± 9.4 μm, and porosity values ranging from 60.2 ± 0.8% to 71.7 ± 2.6%. Human mesenchymal stromal cells (hMSCs) cultured on these scaffolds adhered, proliferated, and produced endogenous extracellular matrix. The effect of surface roughness and topography on hMSCs differentiation was more evident for cells seeded at lower density, where the percentage of cells in direct contact with the surface was higher compared to more densely seeded scaffolds. Under osteogenic conditions, lower surface roughness values (0.227 ± 0.035 μm) had a synergistic effect on hMSCs behavior, while chondrogenesis was favored on rougher surfaces (1.950 ± 0.553 μm).
具有定制表面形貌的增材制造三维（3D）支架在组织再生策略中具有明显的优势，可以控制细胞行为。通过增材制造与湿法纺丝相结合，在无需任何后处理的情况下，成功制备了具有不同纤维表面特征的聚（乙二醇对苯二甲酸酯）/聚（对苯二甲酸丁二醇酯）嵌段共聚物 3D 纤维支架。通过优化加工参数（主要由不同溶剂/非溶剂组合驱动），得到了四种不同类型的支架，其平均表面粗糙度值范围为 0.071 ± 0.012 μm 至 1.950 ± 0.553 μm，x-和 y-轴方向的平均孔径为 351.1 ± 33.6 μm 至 396.1 ± 32.3 μm，z-轴方向的平均孔径为 36.5 ± 5.3 μm 至 70.7 ± 8.8 μm，平均纤维直径为 69.4 ± 6.1 μm 至 99.0 ± 9.4 μm，孔隙率为 60.2 ± 0.8%至 71.7 ± 2.6%。在这些支架上培养的人骨髓间充质干细胞（hMSCs）黏附、增殖并产生内源性细胞外基质。对于接种密度较低的细胞，表面粗糙度和形貌对 hMSCs 分化的影响更为明显，因为与表面直接接触的细胞百分比高于接种密度较高的支架。在成骨条件下，较低的表面粗糙度值（0.227 ± 0.035 μm）对 hMSCs 行为具有协同作用，而在更粗糙的表面上有利于软骨形成（1.950 ± 0.553 μm）。
