骨髓间充质干细胞联合纳米羟基磷灰石胶原蛋白复合支架修复兔节段性骨缺损的实验研究

Experimental Study of Bone Marrow Mesenchymal Stem Cells Combined with Nano-hydroxyapatite Collagen Composite Scaffold for Repairing Segmental Bone Defects in Rabbits

目的:应用骨髓间充质干细胞联合纳米羟基磷灰石胶原蛋白复合支架修复兔尺骨16 mm的缺损,并探讨其对长骨节段性骨缺损的修复效果。方法:选取国产家兔30只(2月龄,体重2~2.5 kg,不限雌雄),随机分为空白组、单纯支架组、实验组,每组10只。家兔双侧尺骨中段建立长16 mm的节段性缺损,空白组骨缺损处不植入任何材料;单纯支架组植入纳米羟基磷灰石胶原蛋白支架;实验组植入骨髓间充质干细胞联合纳米羟基磷灰石胶原蛋白复合支架。分别于术后8、12周时,每组大体观察骨缺损区、X射线观察骨缺损处修复情况、苏木精-伊红染色(HE)组织学观察。结果:术后12周,(1)大体形态观察,空白组骨缺损骨面清晰,骨缺损未能修复;单纯支架组植入材料基本降解,骨缺损部分修复;实验组植入材料大部分降解,材料与宿主骨基本融合,与宿主骨组织结合紧密。(2)X射线影像,空白组仅断端形成少量骨痂,骨缺损周围密度略高;单纯支架组和实验组材料与宿主骨间的界线模糊,皮质连续,髓腔再通,以实验组明显。(3)苏木精-伊红染色分析,空白组见纤维组织形成,骨缺损未修复;单纯支架组材料基本降解,骨缺损区可见骨小梁形成,排列混乱,纤维结缔组织形成,骨缺损基本修复,骨修复不如实验组明显。术后8、12周,实验组X射线骨形成评分均高于空白组和单纯支架组,且单纯支架组均高于空白组,差异均有统计学意义(P<0.05)。结论:通过术后的X射线摄片、大体观察、组织学检查,可以观察到在相同时间段,骨髓间充质干细胞联合纳米羟基磷灰石胶原蛋白复合支架的各观察指标结果均要好于单用纳米羟基磷灰石胶原蛋白支架和不植入任何材料,说明了骨髓间充质干细胞联合纳米羟基磷灰石胶原蛋白复合支架能有效地修复骨缺损。

Objective:To repair of 16 mm defect in the ulna of a rabbit by bone marrow mesenchymal stem cells combined with Nano-hydroxyapatite collagen composite scaffold,and their effects on segmental bone defects of long bones were also investigated.Method:A total of 30 domestic rabbits(2-month-old,2-2.5 kg in weight,no restriction on male and female)were randomly divided into blank group,simple stent group and experimental group,with 10 rabbits in each group.A segmental bone defect of 16 mm were established in the middle ulna of both rabbits,and no material was implanted in the defect of blank group,Nano-hydroxyapatite collagen scaffold was implanted in the simple stent group,the experimental group implanted bone marrow mesenchymal stem cells combined with Nano-hydroxyapatite collagen composite scaffold.At 8 and 12 weeks postoperatively,the bone defect area was observed,the repair of bone defect was observed by X ray and histological observation by hematoxylin-eosin staining(HE)staining.Result:At 12 weeks postoperatively,(1)observation of gross morphology,blank group:the bone surface of the bone defect was clear,and the bone defect could not be repaired;simple stent group:the implanted materials were basically degraded,and the bone defect was partially repaired;experimental group:the implanted material was mostly degraded,and it basically fused with the host bone and tightly bound to the host bone tissue.(2)X-ray images,blank group:only a small amount of callus was formed on the broken ends,and the density around the bone defects was slightly higher;simple stent group and experimental group:indistinct line between material and host bone,continuous cortex,and recanalization of the medullary cavity to be apparent in the experimental group.(3)hematoxylin-eosin staining,blank group:fibrous tissue formation was observed,and the bone defect was not repaired;simple stent group:the materials were basically degraded,and bone trabeculation was observed in the bone defect area,with disorganized arrangement and fibrous connective tissue,the bone defect was basically repaired,and the bone repair was not as significant as that in the experimental group.At 8 and 12 weeks after surgery,X-ray bone formation score of the experimental group was higher than those of the blank group and the simple stent group,and that of the simple stent group were higher than that of the blank group,the differences were statistically significant(P<0.05).Conclusion:During the postoperative period of X-ray radiographs and observation and histological examination,at the same time period,the results of each observation index of bone marrow mesenchymal stem cells combined with Nano-hydroxyapatite collagen composite scaffold were better than those of nano-hydroxyapatite collagen scaffold alone or without any material implantation,showed that the bone marrow mesenchymal stem cells combined with Nano-hydroxyapatite collagen composite scaffold can effectively repairs bone defects.