几种胚胎干细胞标志在牙周膜细胞中的表达及意义

Embryonic stem cell marker expression pattern in human periodontal ligament cells

目的检测部分胚胎干细胞标志在牙周膜细胞中的表达。方法通过酶解组织块法分离牙周膜细胞,利用多向分化实验和流式细胞术分析表面标志对获得细胞进行鉴定。利用免疫荧光法和RT-PCR法检测牙周膜细胞中Oct4、Nanog、Sox2、SSEA-4、TRA-1-60、TRA-1-81这些胚胎干细胞标志的表达。结果牙周膜细胞为成纤维细胞样,可分化为成骨细胞和成软骨细胞,可均一表达间充质细胞标志CD44、CD90、CD105,异质性表达间充质标志CD146、Stro-1。细胞免疫荧光实验显示牙周膜细胞表达部分胚胎干细胞标志:Oct4、Nanog、SSEA-4、TRA-1-60阳性,Sox2、TRA-1-81阴性。半定量RTPCR结果显示P3和P8代牙周膜细胞表达Oct4和Nanog,表达量差异不大,Sox2则为阴性。结论牙周膜细胞除了表达常用间充质干细胞标志外,也可表达部分胚胎干细胞标志,这对牙周膜细胞的鉴定和进一步分选纯化有一定应用价值。

Objective To detect the expression pattern of embryonic stem cell（ESC） markers in human periodontal ligament stem cells （PDLCs）. Methods PDLCs were isolated from human periodontal ligament tissue,and characterized by muhipotent differentiation and cell surface analysis. Immunocytochemistry and RT-PCR were performed to detect the expression of ESC markers （ Oct4 、 Nanog、Sox2,SSEA-4、TRA-1-60,TRA-1-81） in PDLCs. Results PDLCs exhibited typical fibroblast-like morphology,and could differentiate into osteoblasts and chondroblasts. PDLCs homogenously expressed mesenehymal markers of CD44, CD90 and CD105, but heterogenous- ly expressed CD146 and Stro-1. Part of ESC markers was detected in PDLCs. Oct4, Nanog, SSEA-4 and TRA-1-60 were positive in PDLCs while Sox2 and TRA-1-81 were negative. Semi RT-PCR demonstrated similar expression of Oct4 and Nanog in PDLCs of Passage 3 and 8. Howew., Sox2 was negative at the mRNA level. Conclusions Besides mesenchymal stem cells markers,PDLCs could also ex- press parts of ESC markers,which is of certain application value to the identification and purification of periodontal ligament cells.