Department of Spinal Surgery, Orthopedic Medical Center, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China.
Department of Orthopedics, Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
ACS Appl Mater Interfaces. 2022 Jul 6;14(26):29506-29520. doi: 10.1021/acsami.2c04378. Epub 2022 Jun 21.
The repair of large bone defects remains a challenging problem in bone tissue engineering. Ischemia and hypoxia in the bone defect area make it difficult for seed cells to survive and differentiate, which fail to perform effective tissue regeneration. Current oxygen-producing materials frequently encounter problems such as a rapid degradation rate, insufficient mechanical properties, difficult molding, and cumbersome fabrication. Here, a novel three-dimensional (3D) printed integrated bionic oxygenated scaffold was fabricated with gelatin-CaO microspheres, polycaprolactone (PCL), and nanohydroxyapatite (nHA) using low-temperature molding 3D printing technology. The scaffold had outstanding mechanical properties with bionic hierarchical porous structures. reports showed that the scaffold exhibited excellent cytocompatibility and could release O sustainably for more than 2 weeks, which significantly enhanced the survival, growth, and osteogenic differentiation of bone marrow mesenchymal stem cells under hypoxia. experiments revealed that the scaffold facilitated efficient bone repair after it was transplanted into a rabbit calvarial defect model. This result may be due to the scaffolds reducing hypoxia-inducible factor-1α accumulation, improving the expression of osteogenic regulatory transcription factors, and accelerating osteogenesis. In summary, the integrated bionic PCL/nHA/CaO scaffold had excellent capabilities in sustainable O release and bone regeneration, which provided a promising clinical strategy for bone defect repair.
在骨组织工程中，修复大的骨缺损仍然是一个具有挑战性的问题。骨缺损区域的缺血缺氧使得种子细胞难以存活和分化，无法进行有效的组织再生。目前的产氧材料经常遇到快速降解率、机械性能不足、成型困难和制造繁琐等问题。在这里，我们使用低温模压 3D 打印技术，以明胶-CaO 微球、聚己内酯（PCL）和纳米羟基磷灰石（nHA）为原料，制备了一种新型的三维（3D）打印集成仿生氧合支架。该支架具有出色的机械性能和仿生分级多孔结构。研究表明，该支架具有优异的细胞相容性，并能持续释放 O 长达 2 周以上，显著提高了缺氧条件下骨髓间充质干细胞的存活、生长和成骨分化。实验表明，该支架在移植到兔颅骨缺损模型后能有效地促进骨修复。这一结果可能是由于支架减少了缺氧诱导因子-1α 的积累，提高了成骨调节转录因子的表达，并加速了成骨作用。综上所述，集成仿生 PCL/nHA/CaO 支架具有持续 O 释放和骨再生的优异性能，为骨缺损修复提供了一种有前景的临床策略。
