改性纳米羟基磷灰石/聚乳酸-聚羟乙酸复合骨髓基质干细胞修复兔桡骨缺损

背景:前期试验证实骨髓基质干细胞能够在改性纳米羟基磷灰石/聚乳酸-聚羟乙酸材料表面黏附、增殖,该材料具有良好的生物安全性。目的:观察骨髓基质干细胞与改性纳米羟基磷灰石/聚乳酸-聚羟乙酸材料复合修复兔桡骨缺损的效果。方法:建立兔15mm桡骨缺损模型,随机分为3组:空白对照组不进行任何处理,实验组植入改性纳米羟基磷灰石/聚乳酸-聚羟乙酸+骨髓基质干细胞组织工程化骨,对照组植入单纯改性纳米羟基磷灰石/聚乳酸-聚羟乙酸支架材料。结果与结论:①X射线评价:术后1～12周,实验组骨缺损修复程度及速度明显优于空白对照组与对照组(P<0.05)。②组织学检测:实验组术后4周即可观察到新生骨和纤维组织长入材料空隙,局部形成陷窝结构;8周时新生骨组织增多,部分可观察到成熟的骨小梁结构;12周时可见大量成熟骨细胞,骨小梁排列紧密,移植材料逐步被新生骨取代,与正常骨组织形态基本一致,且骨小梁出现时间早于空白对照组与对照组。说明骨髓基质干细胞复合改性纳米羟基磷灰石/聚乳酸-聚羟乙酸构建的组织工程化骨能够促进骨缺损处新骨的生成,较单纯支架材料具有明显优势。

Modified nano-hydroxyapatite/poly (lactide-glycolide acid) combined with bone marrow mesenchymal stem cells for repair of rabbit radial bone defects

BACKGROUND:Practical tests showed that the bone marrow mesenchymal stem cells(BMSCs) could proliferate and adhere on the surface of modifiednano-hydroxyapatite/poly(lactide-glycolide acid)(PLGA/g-HA) that demonstrated that the PLGA/g-HA had a good biocompatibility. OBJECTIVE:To observe the effect of BMSCs combined with modified PLGA/g-HA on repair of rabbit radial bone defect. METHODS:Model of 15 mm rabbit radial bone defect was established.The rabbits were randomly divided into three groups.The blank group was without any treatment,the experimental group was implanted with modified PLGA/g-HA+BMSCs,and the control group was treated with modified PLGA/g-HA. RESULTS AND CONCLUSION:①X-ray evaluation:The extent and speed of repair in the experimental group were obviously increased compared with the blank group and control group after 1-12 weeks of operation(P<0.05) .②Histological observation: At 4 weeks,new formed bone could be seen,fibrous tissue extended into the space of scaffold,and bone lacuna was partially formed in the experimental group;At 8 weeks,new formed bone was increased and mature bone trabecula could be seen in the experimental group;Furthermore,at 12 weeks after operation,a great amount of mature osteoblasts could be seen,trabecular bone tightly packed,and the implants was gradually replaced by normal bone tissues in the experimental group.The experimental group showed its bone trabecula earlier than the blank group and control group.Tissue-engineered bone tissues constructed by BMSCs combined with modified PLGA/g-HA can promote the new bone formation of defect.The BMSCs combined with modified PLGA/g-HA are superior to the simple scaffolds.