小鼠胎肝间充质干细胞的体外成骨诱导及复合陶瓷化骨的实验研究

目的探讨小鼠胚胎肝脏间充质干细胞的体外分离培养方法，并观察其成骨分化潜能及与陶瓷化骨支架材料的复合能力。方法将小鼠胎肝组织制成单细胞悬液行原代和传代培养，流式细胞仪检测其表面标志。用化学成骨诱导体系对纯化的胎肝间充质干细胞行成骨诱导，并进行成骨功能检测。将其与经过Ⅰ型胶原表面改性的陶瓷化骨复合培养，观察细胞在其上的黏附生长情况。结果原代培养的胎肝间充质干细胞，具有集落形成能力，为梭形或多角形。易于传代，传代细胞与原代细胞大小、形态相似。流式细胞仪检测表明，传代后的细胞CD29、CD44阳性，CD34、CD45阴性，表达间充质干细胞的特征标志。成骨诱导7d后碱性磷酸酶染色可见有较多阳性细胞，Ⅰ型胶原免疫组织化学染色呈强阳性；14d后，细胞碱性磷酸酶活性定量检测明显增高；28d后，矿化结节染色呈阳性。将细胞与经胶原表面改性后的煅烧陶瓷化骨复合培养。扫描电镜见载体上有大量细胞黏附于材料表面。结论小鼠胎肝间充质干细胞易于获取及传代；体外成骨诱导后可向成骨细胞方向分化；能在陶瓷化骨支架材料上黏附生长。

EXPERIMENTAL STUDY OF OSTEOGENIC INDUCTION OF FETAL MOUSE LIVER MESENCHYMAL STEM CELLS IN VITRO AND THEIR BIOLOGIC ATTACHMENT PROPERTIES TO TRUE BONE CERAMIC

OBJECTIVE: To study the culture and purification of the fetal mouse liver mesenchymal stem cells (MSCs) in vitro and to investigate their differentiation potential and the composite ability with true bone ceramic(TBC). METHODS: The single cell suspension of MSCs was primarily cultured and passaged, which was prepared from the fetal mouse liver; the flow cytometry was applied to detect CD29, CD34, CD44 and CD45. The osteogenic differentiation was induced in chemical inducing system; the osteogenic induction potency was tested. The purified fetal mouse liver MSCs were compounded with TBC covered with collagen type I in vitro and the cell attachment and proliferation to the TBC were observed. RESULTS: The primary MSCs of fetal mouse liver were easy to culture in vitro. They proliferated well and were easy to subcultured. The proliferation ability of primary and passaged MSCs was similar. Flow cytometric analysis showed the positive results for CD29, CD44 and the negative results for CD34, CD45. After 7 days of induction, the MSCs expressed collagen type I and alkaline phosphatase(ALP) highly. After 14 days of induction, the fixed quantity of ALP increased significantly. After 28 days of induction, calcium accumulation was observed by Von Kossa's staining. Many liver MSCs attached to the surface of TBC. CONCLUSION: The MSCs of the fetal mouse liver can be obtained, subcultured and purified easily. After culturing in chemical inducing system, the MSCs of fetal mouse liver can be successfully induced to osteoblast-like cells, attach to the surface of TBC and proliferate well.