rhBMP_2作用下人牙乳头细胞内Smad1分子的转位变化

目的:观察骨形成蛋白(bone morphogenetic protein)特异的细胞内信号转导分子Smadl在人牙乳头细胞内的表达及信号转位过程,从细胞内信号转导水平探讨牙齿发育过程中成牙本质细胞的分化机制。方法:原代培养人牙乳头细胞,用转化生长因子β1(transforming growth factor β1,TGF-β1)和重组人骨形成蛋白骨形成蛋白2(recombinant hu-man bone morphogenetic protein,rhBMP2)刺激培养的细胞,对照组用0.2％FCS的DMEM的培养液培养,不加任何刺激。免疫组化观察。结果: TGF-β1和rhBMP2刺激组均可见Smadl蛋白表达,但与对照组相比无明显差异;rhBMP2组可见Smadl从胞浆转位至核内聚集,TGF-β1组未见此作用。结论:首次观察到Smadl基因在人牙乳头细胞内的表达并参与信号转位过程,提示BMP2在牙乳头细胞内信号传递可能是通过Smadl转位至核内引起基因表达实现的。

The Translocation of Smad1 in the Dental Papilla Cells Treated by rhBMP2

Objective: The aim of this study was to investigate the expression of Smadl gene in human dental papillae cells (HDPC) and the transduction process and, to explore the molecular mechanism of odontoblast differentiation during tooth development process at a signaling transduction level. Methods: Immunohistochemical staining of HDPC derived from primary culture stimulated by transforming growth factor B1(TGF-B1) and recombinant human bone morphogenetic protein (rhBMP2) were used in this investigation. Results: The expression of protein of Smadl gene was found in HDPC stimulated by TGF-ji and rhBMP2 , but no significant difference was found between these experimental groups and the control group. Smad2 was found nuclear translocation accumulation form cytoplasm, when HDPC were treated by rhBMP2 .Conclusion: The expression and translocation accumulation of the protein of Smadl gene in HDPC were detected at the first time. The signaling transduction of rhBMP2 in dental papilla cells could be mediated by Smadl translocation and accumulation in nucleus.