Li Ruiquan, McCarthy Alec, Zhang Yu Shrike, Xie Jingwei
Department of Surgery-Transplant and Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE, 68130, USA.
Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA.
Adv Biosyst. 2019 Dec;3(12):e1900137. doi: 10.1002/adbi.201900137. Epub 2019 Nov 4.
Repairing large tissue defects often represents a great challenge in clinics due to issues regarding lack of donors, mismatched sizes, irregular shapes, and immune rejection. 3D printed scaffolds are attractive for growing cells and producing tissue constructs because of the intricate control over pore size, porosity, and geometric shape, but the lack of biomimetic surface nanotopography and limited biomolecule presenting capacity render them less efficacious in regulating cell responses. Herein, a facile method for coating 3D printed scaffolds with electrospun nanofiber segments is reported. The surface morphology of modified 3D scaffolds changes dramatically, displaying a biomimetic nanofibrous structure, while the bulk mechanical property, pore size, and porosity are not significantly compromised. The short nanofibers-decorated 3D printed scaffolds significantly promote adhesion and proliferation of pre-osteoblasts and bone marrow mesenchymal stem cells (BMSCs). Further immobilization of bone morphogenetic protein-2 mimicking peptides to nanofiber segments-decorated 3D printed scaffolds show enhanced mRNA expressions of osteogenic markers Runx2, Alp, OCN, and BSP in BMSCs, indicating the enhancement of BMSCs osteogenic differentiation. Together, the combination of 3D printing and electrospinning is a promising approach to greatly expand the functions of 3D printed scaffolds and enhance the efficacy of 3D printed scaffolds for tissue engineering.
由于供体缺乏、尺寸不匹配、形状不规则以及免疫排斥等问题，修复大面积组织缺损在临床上常常是一项巨大的挑战。3D打印支架因能精确控制孔径、孔隙率和几何形状，对细胞生长和组织构建颇具吸引力，但缺乏仿生表面纳米拓扑结构和有限的生物分子呈现能力使其在调节细胞反应方面效果欠佳。在此，报道了一种用静电纺丝纳米纤维片段包覆3D打印支架的简便方法。改性3D支架的表面形态发生显著变化，呈现出仿生纳米纤维结构，而其整体力学性能、孔径和孔隙率并未受到明显影响。短纳米纤维修饰的3D打印支架显著促进前成骨细胞和骨髓间充质干细胞（BMSC）的黏附与增殖。将骨形态发生蛋白-2模拟肽进一步固定到纳米纤维片段修饰的3D打印支架上，显示BMSC中成骨标志物Runx2、Alp、OCN和BSP的mRNA表达增强，表明BMSC成骨分化增强。总之，3D打印与静电纺丝相结合是一种很有前景的方法，可极大地扩展3D打印支架的功能并提高其在组织工程中的效能。
