血管内皮祖细胞对组织工程骨成骨能力的影响

An experimental study of endothelial progenitor cells on bone formation in tissue-engineered bone in dogs

目的:观察血管内皮祖细胞(endothelial progenitor cells,EPCs)在实验犬体内构建组织工程骨时对其成骨能力的影响。方法:抽取实验犬骨髓,密度梯度离心法获取单个核细胞,通过不同培养方法获得经成骨诱导的骨髓间充质干细胞(bone marrow stromal cells,BMSCs)和EPCs,在体外复合犬同种异体脱钙骨基质(demineralized bone matrix,DBM),扫描电镜和相差显微镜观察细胞形态和生长情况;将复合体植入实验犬背阔肌筋膜下,右侧为实验组,植入EPCs/BMSCs/DBM复合体,左侧为对照组,植入BMSCs/DBM复合体。影像学和组织学方法观察术后不同时间点组织工程骨的骨形成程度。采用SPSS13.0软件包对所得数据进行t检验。结果:术后4、8、12周,X线显示实验组的骨密度显著高于对照组,差异有统计学意义(P<0.05);组织学观察显示,实验组成骨多于对照组,2组新生骨面积及血管面积之间差异有统计学意义(P<0.05)。结论:EPCs可以促进组织工程骨的成骨能力,加速新生骨形成。

PURPOSE： To observe the effects of endothelial progenitor cells（EPCs） on bone formation of tissue engineered bone in dogs.METHODS： Bone marrow stromal cells（BMSCs） and EPCs were derived from dog bone marrow and cultured in different medium in vitro.They were seeded on demineralized bone matrix（DBM） to build tissue engineered bone,then the construct was implanted into the fasciae of latissimus dorsi muscle,the degree of bone formation was analyzed with imaging and histological methods at different time points.SPSS13.0 software package was used for statistical analysis.RESULTS： 4,8,12 weeks after operation,X-ray film showed bone mineral density（BMD） in the EPCs group was significantly higher than the control group,and there was significant difference between the two groups（P〈0.05）;Histological examination revealed that the degree of bone formation in the EPCs group was higher than the control group,the new bone area and blood vessel area between the two groups were significantly different（P〈0.05）.CONCLUSION： EPCs can promote bone formation and accelerate new bone formation in tissue-engineering bone.Supported by National Natural Science Foundation of China（30872896） and Natural Science Foundation of Shandong Province（Y2008C77）.