Wang Chenglong, Dong Jinlei, Liu Fanxiao, Liu Nan, Li Lianxin
Department of Orthopaedics Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250021, China.
Department of Orthopaedics Surgery, Shandong Trauma Center, Jinan, 2500021, China.
J Biol Eng. 2024 Jan 2;18(1):1. doi: 10.1186/s13036-023-00401-4.
The long-term nonunion of bone defects is always a difficult problem in orthopaedics treatment. Artificial bone implants made of polymeric materials are expected to solve this problem due to their suitable degradation rate and good biocompatibility. However, the lack of mechanical strength, low osteogenic induction ability and poor hydrophilicity of these synthetic polymeric materials limit their large-scale clinical application.
In this study, we used bioactive glass (BG) (20%, W/W) and polycaprolactone (PCL, 80%, W/W) as raw materials to prepare a bone repair scaffold (PCL@BG20) using fused deposition modelling (FDM) three-dimensional (3D) printing technology. Subsequently, stromal cell-derived factor-1α (SDF-1α) chemokines were loaded into the PCL@BG20 scaffold pores with gelatine methacryloyl (GelMA) hydrogel. The experimental results showed that the prepared scaffold had a porous biomimetic structure mimicking that of cancellous bone, and the compressive strength (44.89 ± 3.45 MPa) of the scaffold was similar to that of cancellous bone. Transwell experiments showed that scaffolds loaded with SDF-1α could promote the recruitment of bone marrow stromal cells (BMSCs). In vivo data showed that treatment with scaffolds containing SDF-1α and BG (PCL@BG-GelMA/SDF-1α) had the best effect on bone defect repair compared to the other groups, with a large amount of new bone and mature collagen forming at the bone defect site. No significant organ toxicity or inflammatory reactions were observed in any of the experimental groups.
The results show that this kind of scaffold containing BG and SDF-1α serves the dual functions of recruiting stem cell migration in vivo and promoting bone repair in situ. We envision that this scaffold may become a new strategy for the clinical treatment of bone defects.
骨缺损的长期不愈合一直是骨科治疗中的难题。由聚合材料制成的人工骨植入物因其合适的降解速率和良好的生物相容性有望解决这一问题。然而，这些合成聚合材料缺乏机械强度、成骨诱导能力低且亲水性差，限制了它们的大规模临床应用。
在本研究中，我们以生物活性玻璃（BG，20%，重量/重量）和聚己内酯（PCL，80%，重量/重量）为原料，采用熔融沉积建模（FDM）三维（3D）打印技术制备了一种骨修复支架（PCL@BG20）。随后，将基质细胞衍生因子-1α（SDF-1α）趋化因子与甲基丙烯酰化明胶（GelMA）水凝胶一起载入PCL@BG20支架孔隙中。实验结果表明，制备的支架具有模仿松质骨的多孔仿生结构，支架的抗压强度（44.89±3.45兆帕）与松质骨相似。Transwell实验表明，载入SDF-1α的支架可促进骨髓间充质干细胞（BMSC）的募集。体内数据显示，与其他组相比，用含有SDF-1α和BG的支架（PCL@BG-GelMA/SDF-1α）治疗对骨缺损修复效果最佳，在骨缺损部位形成了大量新骨和成熟胶原蛋白。在任何实验组中均未观察到明显的器官毒性或炎症反应。
结果表明，这种含有BG和SDF-1α的支架具有在体内募集干细胞迁移和促进原位骨修复的双重功能。我们设想这种支架可能成为骨缺损临床治疗的新策略。
