Pei Yazhen, Liu Xi, Liu Shanshan, Lu Qiang, Liu Jing, Kaplan David L, Zhu Hesun
National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China.
National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, People's Republic of China.
Acta Biomater. 2015 Feb;13:168-76. doi: 10.1016/j.actbio.2014.11.016. Epub 2014 Nov 15.
Three-dimensional (3-D) porous silk scaffolds with good biocompatibility and minimal immunogenicity show promise in a range of tissue regeneration applications. However, the challenge remains to effectively fabricate their microstructures and mechanical properties to satisfy the specific requirements of different tissues. In this study, silk scaffolds were fabricated to form an extracellular matrix (ECM) mimetic nanofibrous architecture using a mild process. A slowly increasing concentration process was applied to regulate silk self-assembly into nanofibers in aqueous solution. Then glycerol was blended with the nanofiber solution and induced silk crystallization in the lyophilization process, endowing freeze-dried scaffolds with water stability. The glycerol was leached from the scaffolds, leaving a similar porous structure at the micrometer scale but different topographies at the nanoscale. Compared to previous salt-leached and methanol-annealed scaffolds, the present scaffolds showed lower β-sheet content, softer mechanical property and improved cell growth and differentiation behaviors, suggesting their promising future as platforms for controlling stem cell fate and soft tissue regeneration.
具有良好生物相容性和最小免疫原性的三维（3-D）多孔丝支架在一系列组织再生应用中显示出前景。然而，有效地制造其微观结构和机械性能以满足不同组织的特定要求仍然是一个挑战。在本研究中，采用温和的工艺制备丝支架以形成细胞外基质（ECM）模拟纳米纤维结构。应用缓慢增加浓度的过程来调节丝在水溶液中自组装成纳米纤维。然后将甘油与纳米纤维溶液混合，并在冻干过程中诱导丝结晶，赋予冻干支架水稳定性。甘油从支架中浸出，在微米尺度上留下类似的多孔结构，但在纳米尺度上具有不同的形貌。与先前的盐浸和甲醇退火支架相比，目前的支架显示出较低的β-折叠含量、较软的机械性能以及改善的细胞生长和分化行为，表明它们作为控制干细胞命运和软组织再生平台具有广阔的前景。
