Department of Mechanical Engineering, Biomanufacturing Center, Tsinghua University, Beijing, China.
Biomanufacturing and Rapid Forming Technology, Key Laboratory of Beijing, Beijing, China.
J Biomed Mater Res A. 2019 Dec;107(12):2694-2705. doi: 10.1002/jbm.a.36773. Epub 2019 Aug 19.
From a structural perspective, an ideal scaffold ought to possess interconnected macro pores with sizes from 10 to 100 μm to facilitate cell infiltration and tissue formation, as well as similar topography to the natural extracellular matrix (ECM) which would have an impact on cell behavior such as cell adhesion and gene expression. For that purpose, here we developed a fabrication process to incorporate electrospun short fibers within freeze-dried scaffolds for tissue engineering applications. Briefly, PCL short fibers were first produced from electrospun fibers with ultrasonication method. They were then evenly dispersed in gelatin solution and freeze-dried to obtain fiber incorporated scaffolds. The resulting scaffolds exhibited hierarchical structure including major pores with sizes ranging from 50 to 150 μm and the short fibers dispersed in the thin walls of major pores, mimicking the fibrous feature of natural ECM. The short fibers were proven to modify the mechanical properties of scaffold and to facilitate cell adhesion and proliferation on the scaffold. As a promising scaffold for tissue engineering and regenerative medicine, the fiber incorporated scaffold may have further biomedical applications, in which the short fibers can act as drug release vehicles for growth factors or other biomolecules to promote vascularization.
从结构的角度来看，理想的支架应该具有相互连接的大孔，尺寸为 10 到 100μm，以促进细胞渗透和组织形成，以及类似于天然细胞外基质 (ECM) 的形貌，这将对细胞行为产生影响，如细胞黏附和基因表达。为此，我们在这里开发了一种制造工艺，将静电纺短纤维纳入组织工程应用的冻干支架中。简而言之，首先通过超声方法从静电纺纤维中生产出 PCL 短纤维。然后，它们均匀分散在明胶溶液中并冻干以获得纤维掺入的支架。所得支架表现出分层结构，包括尺寸为 50 到 150μm 的大孔和分散在大孔薄壁中的短纤维，模拟了天然 ECM 的纤维特征。短纤维被证明可以改变支架的机械性能，并促进细胞在支架上的黏附和增殖。作为组织工程和再生医学的有前途的支架，纤维掺入的支架可能具有进一步的生物医学应用，其中短纤维可以作为生长因子或其他生物分子的药物释放载体，以促进血管生成。
