牙囊干细胞诱导成骨的体外研究

目的:体外研究牙囊干细胞(DFSC)的成骨能力,为其在牙周组织工程中的应用提供理论基础。方法:结合组织块法和酶消化法分离培养DFSC,用有限稀释法纯化细胞,经细胞形态、免疫组化和流式细胞技术鉴定DFSC后,然后进行成骨诱导,并通过碱性磷酸酶和茜素红染色、Real-timePCR、Western-blot检测成骨/牙骨质细胞表面标记物ALP、OCN、BMP2、RUNX2的表达。结果:DFSC具有较强的增殖能力,免疫组化示波形丝蛋白表达阳性,角蛋白表达阴性;DFSC高表达间充质干细胞表面标记物CD44、CD90、CD105、CD146;随着诱导时间的增加,其ALP、OCN、BMP2、RUNX2的表达明显上调(P＜0.05)。结论:DFSC是牙周组织再生良好的种子细胞,必将为牙周组织再生治疗开辟新的途径。

Osteogenesis of Human Dental Follicle Stem Cells in Vitro

Objective: To observe the osteogenesis of human dental follicle stem cells(DFSC) in osteogenic medium in vitro. Methods: DFSCs were primarily cultured by tissue and digestion method. Cells were passaged and identified by stem cell surface marker expression using immunohistochemistry and flow cytometry. After osteogenesis induction,osteogenesis ability of the cells was determined with alkaline phosphate (ALP) and Alizarin Red S staining, real time quantitative PCR and western blot. Results: DFSCs showed strong reproductive activity. And the immunohistochemistry staining showed that vimentin expression in DFSCs was positive, while cytokeratin 14 was negative. High expression of mesenchymal stem cell markers CD44, CD90, CD105 and CD146 was detected in DFSCs. Under osteogenesis induction, DFSCs could express osteogenesis or cementoblast cell markers ALP, OCN, BMP2 and RUNX2 in vitro(P＜0.05). Conclusion: DFSC might be a novel candidate for the treatment of periodontal defects in periodontal tissue engineering.