中文摘要：

目的比较ALX基因家族成员（ALX1，ALX3，ALX4）在人胚胎干细胞（hESCs）及其来源神经嵴细胞（NCCs）和NCCs分化得到的外周神经元细胞和间充质干细胞（MSCs）中的表达水平，为了解NCCs分化过程中ALX基因家族的表达调控提供研究基础。方法利用RT—PCR、免疫荧光染色、流式细胞分析技术及体外分化实验，鉴定hESCs、NCCs、外周神经细胞和MSCs的生物学特性；应用Real—timePCR比较ALX基因家族成员在不同分化细胞中的表达水平。结果ALXl在MSCs中的表达明显低于在hESCs和NCCs中；ALX3特异性地在MSCs中高表达；ALX4在外周神经细胞、MSCs及其分化的成骨细胞中高表达。结论不同的ALX基因家族成员在不同分化阶段的细胞中有不同的表达谱，提示它们在不同细胞中的表达调控存在差异。

英文摘要：

Objective To compare the expressions of ALX gene family members （ ALX1, ALX3, ALX4） in human embryonic stem cells （hESCs） and their differentiated neural crest cells （NCCs）, as well as human mesenchymal stem cells （MSCs） and peripheral neurons derived from NCCs. The result provided a research foundation for understanding the expressions of ALX gene family in the process of NCCs differentiation. Methods The characteristics of hESCs, NCCs, MSCs and peripheral neurons were identified by RT-PCR, immunofluorescence staining and flow cytometry analysis. The expressions of ALX1, ALX3 and ALX4 were quantified by Real-time PCR. Results The expressions of ALX1 were significantly lower in MSCs than in NCCs （P 〈 0.05）. However, the expression of ALX3 was significantly higher in MSCs than in hESCs, NCCs, peripheral neurons and osteoblasts （P 〈 0. 05）. The expressions of ALX4 were higher in MSCs, peripheral neurons and osteoblasts. Conclusions The expression profiles of different ALX genes in stem cells at different development stages are different, suggesting the regulation of ALX genes expressions is different in diverse ceils.