中文摘要：

该实验以人脐带间充质干细胞（human umbilical cord mesenchymal stem cells，hUCM—SCs）为研究对象，探讨维生素A对其体外培养的影响。结果显示，添加维生素A培养后，hUCMSCs仍维持其本身生物学特性，表达其标记基因CD29、CD44和干细胞标记基因Oct4、Sox2、Nanog。维生素A促进hUCMSCs的体外增殖，上调增殖基因PCNA、C-myc和干细胞标记基因Nanog的表达，下调凋亡基因Bch的表达。该研究证明了维生素A具有促进hUCMSCs增殖和维持其干细胞特性的作用，对继续探索hUCMSCs的体外快速增殖和维生素A对hUCMSCs增殖调控的机理具有重要意义。

英文摘要：

This work was designed to investigate the effects of vitamin A on the proliferation of human umbilical cord mesenchymal stem cells （hUCMSCs）. The results showed that after in vitro treatment ofhUCMSCs with vitamin A, the biological characteristics of hUCMSCs could be performed. The expression patterns of hUCMSCs markers and stem cell markers, including CD29, CD44, Oct4, Sox2 and Nanog, were also detected. In addition, we confirmed that vitamin A could stimulate the proliferation of hUCMSCs. The transcriptions of biomolecules, such as PCNA, C-myc and Nanog, were significantly elevated, while the transcript of Bcl-x declined. It was identified that the vitamin A could trigger the characteristics maintenance and proliferation of hUCMSCs, which might be crucial to reveal the regulation mechanism of vitamin A on the proliferation ofhUCMSCs.