SOX2对牙髓干细胞神经分化的促进作用及其意义

目的：探讨转录因子SOX2对牙髓干细胞（DPSCs）神经分化的影响，为研究DPSCs神经分化的机制提供依据。方法：从人源第三磨牙牙髓中分离DPSCs（DPSCs组），通过逆转录病毒感染方法构建过表达SOX2的DPSCs（DPSCs-SOX2组），以空白载体感染的DPSCs作为对照组（DPSCs-vector组），采用神经分化培养基诱导各组DPSCs分化为神经前体细胞（NPCs）。采用CCK-8法分析各组NPCs的增殖指数（PI）；采用qPCR和流式细胞术检测各组NPCs中Nestin和Pax6基因的表达水平；采用免疫荧光和流式细胞术分析各组NPCs在神经元分化方面的能力和分化后β3-Tubulin的表达效率。结果：通过神经分化培养基的定向诱导，正常DPSCs、DPSCs-vector和DPSCs-SOX2均可通过分化形成NPCs，但DPSCs-SOX2组NPCs的PI和NPCs中Nestin和Pax6表达水平明显高于DPSCs组和DPSCs-vector组（P<0.05）；DPSCs-SOX2组NPCs在神经元分化方面也具有一定的优势，分化后细胞的β3-Tubulin表达效率明显高于其他2组（P<0.05）。结论：SOX2对DPSCs的神经分化具有一定的促进作用。

Promotive effect of SOX2 on neural differentiation of dental pulp stem cells and its significance

Objective:To explore the effect of SOX2 on the neural differentiation of dental pulp stem cells (DPSCs),and to provide basis for studying the mechanism of neural differentiation of DPSCs.Methods:The DPSCs (DPSCs group)were isolated from human dental pulp of third molar,and the SOX2 over exression DPSCs (DPSCs-SOX2 group)were established via retrovirus infection.The empty vector-infected DPSCs (DPSCs-vector group)were regarded as control group.The DPSCs in various groups were induced into neural progenitor cells (NPCs)by neural differentiation medium.The proliferation index (PI)of NPCs in various groups was evaluated by CCK-8 method;the expression levels of Nestin and Pax6 gene in NPCs in various groups were detected by qPCR and FACS;the differentiation abilities of NPCs and the expression efficiencies ofβ3-Tubulin after differentiation in various groups were evaluated by immunofluorescence and FACS methods.Results:All of normal DPSCs,DPSCs-vector and DPSCs-SOX2 derived from NPCs could be differentiated into NPCs successfully through the induction of neural differentiation medium.Compared with DPSCs and DPSCs-vector groups,the PI of DPSCs in DPSCs-SOX2 group was increased (P<0.05),and the expression levels of Nestin and Pax6 in NPCs were increased (P<0.05). The expression efficiency ofβ3-Tubulin in differentiated NPCs in DPSCs-SOX2 group was higher than those in DPSCs and DPSCs-vector groups (P<0.05).Conclusion:SOX2 could have a certain promotive effect on the neural differentiation of DPSCs.