中文摘要：

通过外源表达人端粒酶基因，构建了具有长期传代能力的骨髓间充质干细胞系（hTERT-hMSC），并在传代过程中尚未发现有丧失接触性生长抑制和转型现象．本文主要目的是采用双向凝胶电泳技术和MALDI-TOF-MS蛋白质谱技术分析hTERT-hMSC细胞的蛋白差异表达图谱，研究表达外源端粒酶基因对骨髓间充质干细胞生物学特性影响的可能机制．通过分析原代第12代hMSC、第95代和275代hTERT-hMSC的蛋白凝胶图，获得原代第12代hMSC总共1543±145个蛋白点，第95代hTERT-hMSC1611±186个蛋白点、275代hTERT-hMSC1451±126个蛋白点．质谱分析鉴定100种蛋白质，其中有20种有显著差异表达．结果表明，膜联蛋白（ANX）和GSTP1表达的下调以及内质网钙结合蛋白1（RCN1）、伴侣素CCT、TUBA1B和ACTG1表达的上调可能提升了人骨髓间充质干细胞扩增的能力，而prohibitin蛋白和p53蛋白维持正常表达可能对hTERT-hMSC维持细胞接触性生长抑制起着重要作用．

英文摘要：

Previous report of the tumorigenicity of human mesenchymal stem cells （hMSC） transduced with exogenous human telomerase reverse transcriptase （hTERT） has been a great concern in the clinical application of stem cells. However, we have obtained a line of hMSC transduced with hTERT （hTERT-hMSC） that presented no tumorigenicity following long-term cultures of 290 population doublings （PD）. To explore the possible anti-tumorigenic mechanism in hTERT-hMSC, we investigated the protein expression profile of hTERT-hMSC compared to hMSC during the cultivation process by two-dimensional gel electrophoresis （2-DE） and pepfide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. From proteome maps of primary hMSC and hTERT-hMSC, we detected 1 543 ± 145 protein spots on the 2D-gels of primary MSCs at PD 12, 1 611 ± 186 protein spots in the gels of hTERT-hMSC at PD 95 and 1 451 ± 126 protein spots in the gels of hTERT-hMSC at 275 PD. Among the most differentially expressed 20 proteins, RCN1, CCT, TUBA1B and ACTG1 were up-regulated, whereas ANX and GSTP1 were down-regulated. This would be presumably in favor of the proliferation of MSCs for long-term culture. Meanwhile, the sustained expression of prohibitin and P53 in hTERT-hMSC might contribute to the inhibition of proliferation-associated transforming activity.