目的 :为组织工程研究作准备 ,分离大鼠骨髓单个核细胞并诱导培养向内皮分化。方法 :成年SD大鼠 ,应用Ficoll淋巴细胞分离液 (密度1 .0 77g/ml) ,将长骨骨髓经非连续密度梯度离心 ,收集中层的单个核细胞 ,加入诱导培养基并置于纤维连接素包被的培养板上进行诱导分化 ,观察细胞生长状况 ,以透射电镜及Ⅷ因子、CD3 1、Lectin免疫组化以及流式细胞仪方法对培养细胞进行鉴定。结果 :细胞圆形、纺锤形单层融合贴壁生长 ;Ⅷ因子、CD3 1、Lectin免疫组化染色阳性 ;透射电镜显示细胞具有内皮特征性的Weibel Palade小体。结论 :采用Ficoll密度梯度离心可获得较高纯度的骨髓单个核细胞 ,经体外培养并诱导分化 ,具有血管内皮细胞的特征 OBJECTIVE: To prepare tissue engineering studies, isolate rat bone marrow mononuclear cells and induce culture to differentiate into endothelial cells. METHODS: Adult Sprague-Dawley rats were exposed to Ficoll lymphocytes (density 1.77 g / ml). The bone marrow of long bone was centrifuged by non-continuous density gradient. The middle mononuclear cells were harvested and cultured in induction medium and placed on fibronectin On the coated plates, the cells were induced to differentiate and the growth of the cells was observed. The cultured cells were identified by transmission electron microscopy and factor Ⅷ, CD3 1, Lectin immunohistochemistry and flow cytometry. RESULTS: The cells were round and spindle-shaped with monolayer fusion and adhesion growth. The Ⅷ factor, CD3 1 and Lectin immunohistochemical staining were positive. The endothelial cells were characterized by Weibel Palade bodies by transmission electron microscopy. Conclusion: Ficoll density gradient centrifugation can obtain higher purity of bone marrow mononuclear cells, cultured in vitro and induced differentiation, with the characteristics of vascular endothelial cells