诱导成牙本质样细胞在体内外的矿化研究

Mineralization of induced odontoblast-like cells from facial ectomesenchymal cells in vivo and in vitro

目的 :人早期胚胎颌突外胚间充质细胞在体外能被诱导分化为成牙本质样细胞 ,表达牙本质特异的涎磷蛋白。本研究探讨该诱导分化细胞在体内外矿化的可能。方法 :转化生长因子 - β1(TGF - β1)和牙本质非胶原蛋白 (DNCP)作用于三维培养的外胚间充质细胞 ,诱导 10d ,然后将诱导的成牙本质样细胞接种于裸鼠皮下 ,X线照相 ,组织切片 ,HE染色 ,观察细胞在体内的矿化情况。同时消化细胞 ,培养于矿化液中 ,观察细胞在体外的矿化能力。结果 :8周后 ,裸鼠皮下接种的胶原细胞密度明显高于对照组。 5周 ,胶原内的细胞为单极长突起 ;8周时 ,细胞周围可见牙本质样基质结构沉积。矿化液中的细胞 3d出现复层生长 ,2 1d ,VonKossa染色阳性。结论 :诱导的成牙本质样细胞在体内可以形成类似牙本质样基质 ,在体外能形成矿化结节 ,为有功能的终末分化的成牙本质细胞。

AIM:To investigate the mineralization ability of induced odontoblast-like cells from facial ectomesenchymal cells in vivo and in vitro .METHODS:Induced odontoblast-like cells from ectomesenchymal cells by transforming growth factor β1(TGF-β1) and dentin non-collagen proteins (DNCP) in gel were implanted subcutaneously in null mice. Radiography for sign of mineralization was performed at 8 weeks. At 5 and 8 weeks, cells were removed and stained by hematoxylin and eosin.At 10th day, cells were extracted and cultured in mineralization medium.Von Kossa stain was used to test the formation of mineralized nodules.RESULTS:8 weeks later in vivo , the density of tissue with odontoblast-like cells was higher than that of the control. At 5 weeks, the cells were columnar with long processes. At 8 weeks, there were some mineralized dentin-like matrix deposition around cells. In vitro, cells in mineralized medium could formed mineralized nodules.CONCLUSION:The induced odontoblast-like cells in gel was terminal differentiaed cells which had mineralization ability to synthesis dentin-like matrix in vivo and vitro .