MIRA Institute for Biomedical Technology and Technical Medicine, Department of Polymer Chemistry and Biomaterials, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Acta Biomater. 2010 Nov;6(11):4208-17. doi: 10.1016/j.actbio.2010.06.012. Epub 2010 Jun 16.
The advance of rapid prototyping techniques has significantly improved control over the pore network architecture of tissue engineering scaffolds. In this work, we have assessed the influence of scaffold pore architecture on cell seeding and static culturing, by comparing a computer designed gyroid architecture fabricated by stereolithography with a random pore architecture resulting from salt leaching. The scaffold types showed comparable porosity and pore size values, but the gyroid type showed a more than 10-fold higher permeability due to the absence of size-limiting pore interconnections. The higher permeability significantly improved the wetting properties of the hydrophobic scaffolds and increased the settling speed of cells upon static seeding of immortalised mesenchymal stem cells. After dynamic seeding followed by 5 days of static culture gyroid scaffolds showed large cell populations in the centre of the scaffold, while salt-leached scaffolds were covered with a cell sheet on the outside and no cells were found in the scaffold centre. It was shown that interconnectivity of the pores and permeability of the scaffold prolonged the time of static culture before overgrowth of cells at the scaffold periphery occurred. Furthermore, novel scaffold designs are proposed to further improve the transport of oxygen and nutrients throughout the scaffolds and to create tissue engineering grafts with a designed, pre-fabricated vasculature.
快速原型制造技术的进步显著改善了组织工程支架的孔网络结构的控制。在这项工作中，我们通过比较由立体光刻制造的计算机设计的介晶结构和由盐浸出产生的随机孔结构，评估了支架孔结构对细胞接种和静态培养的影响。这两种支架类型具有可比的孔隙率和孔径值，但由于不存在尺寸限制的孔连通性，介晶型的渗透性要高 10 倍以上。较高的渗透性显著改善了疏水支架的润湿性，并增加了在静态接种永生化间充质干细胞时细胞的沉降速度。在动态接种后进行 5 天的静态培养后，介晶支架在支架中心显示出大量的细胞群体，而盐浸出的支架在外部覆盖有细胞层，而在支架中心则没有发现细胞。结果表明，孔的连通性和支架的渗透性延长了在支架外围细胞过度生长之前的静态培养时间。此外，还提出了新的支架设计方案，以进一步改善氧气和营养物质在整个支架中的传输，并创建具有设计的预制脉管系统的组织工程移植物。
