摘要:
BACKGROUND:In vitro culture of tissue-engineered bone is an important method for bone repair. Three-dimensional (3D) printed bone stents combined with bioreactor culture are of significance in bone tissue engineering. OBJECTIVE:To study thein vivo repair effect of the 3D printed biomaterial scaffold with human mesenchymal stem cells (hMSCs) cultured in bioreactor. METHODS:The scaffold was constructed by poly(lactic-co-glycolic acid)/hydroxyapatite (PLGA/HA)via 3D printing and freeze-dying techniques, and then hMSCs were seeded onto the scaffold and cultured in bioreactors. Al rabbits were numbered and divided into control (No.1 and 2), experimental 1 (No. 3 and 4) and experimental 2 (No. 5 and 6) groups, and each group had two subgroups positive and negative. The rabbit left distal femur in each group was modeled into bone defect and the single PLGA/HA scaffold, PLGA/HA scaffold carrying non-induced hMSCs were implanted in the positive and negative groups of the control group, respectively; the PLGA/HA-201405-1 and PLGA/HA-201405-2carrying induced hMSCs were implanted into the positive and negative subgroups of the experimental 1 and 2 groups, respectively. Additionaly, the right femur in the experimental 2 group was driled only. The osteogenesis ability and biodegradability were determined using electron microscope, thein vivorepair was observed through CT examination, and the histopathological examination was performed after bone healing. RESULTS AND CONCLUSION:The scaffold with topological structure suitable for cellseeding was prepared. A large number of new calcium nodules were observed under electron microscope in the experimental groups indicating overt achievement in bone healing. These results suggest that the prepared scaffold achieves a good repair effect preliminarily.%背景:体外培养组织工程骨仍是治疗骨缺损修复的重要途径,3D打印骨架材料结合生物反应器骨组织是骨组织工程的重要研究内容.目的:观察3D打印制备的生物骨支架接种细胞后经生物反应器立体培养体内修复骨伤的效果.方法:①配制生物骨材料聚乳酸-羟基乙酸共聚物/羟基磷灰石(PLGA/HA),3D打印和冷冻干燥技术制备骨架,接种人骨髓间充质干细胞、经生物反应器培养分化;②实验动物分为3组,分别为对照组(1号,2号),实验组(3号,4号),实验+空孔组(5号,6号,均行右股骨钻孔不植入任何材料);每组又分为2个亚组并编号.兔左侧股骨远端制作骨缺损模型,对照组分别植入空白材料-PLGA/HA(无细胞)和阴性材料PLGA/HA(接种人骨髓间充质干细胞)无诱导分化的支架块;实验组材料-PLGA/HA为接种人骨髓间充质干细胞经诱导分化的支架块,批号分别为201405-1和201405-2;③电子显微镜确定生物骨材料的成骨和降解性能.CT扫描生物骨体内修改效果,待受试组的骨破损基本修复后,做组织病理学检查.结果与结论:制备出适于细胞种植的具有拓扑结构的生物骨支架;电子显微镜观察成骨干细胞附着的生物骨材料立体化培养后形成的新骨节点明显;在支架植入家兔体内后,有明显促进成骨愈合的作用.结果显示制备的生物骨组织材料达到了初步的修复骨组织的作用.