bFGF诱导脐血CD_(34)^+干细胞基因表达变化的研究

bFGF induced changes in gene expression of human umbilical cord blood CD_(34)^+ stem cells using oligonucleotide microarrays

目的探讨碱性成纤维细胞生长因子(bFGF)体外诱导脐血CD34+造血干细胞分化的基因表达变化,理解脐血CD34+造血干细胞的生物学特性,为体外诱导分化和临床应用打下基础。方法利用MiniMACS免疫磁珠法从脐静脉血单个核细胞中分离出CD34+造血干细胞,经含干细胞因子(SCF)、bFGF、B27的DMEM/F12细胞营养液培养10～15d,提取培养前后细胞总RNA,利用Oligo GEArray芯片和GEArray表达分析软件进行芯片数据分析。结果在所检测的263个基因中,发现10个基因培养后比培养前显著上调,20个基因显著下调。这些基因主要涉及干细胞特异性标志、细胞周期、干细胞分化标志、以及与干细胞相关的信号转导、细胞因子及其受体等。结论bFGF通过一些特定基因的变化影响脐血CD34+干细胞增殖分化,有助于从基因水平理解bFGF对CD34+干细胞增殖分化的影响,促进bFGF诱导的CD34+细胞在临床上的应用。

【Objective】To study on the bFGF induced changes in gene expression of human umbilical cord blood CD34^＋ stem cells and understanding its characteristics for potentially use in regenerative medicine. 【Methods】Human umbilical cord blood CD34^＋ stem cells were isolated and purified by MACS magnetic selection. The CD34^＋ cells were cultured for 10 to 15 days in DMEM/F12 medium included SCF,bFGF and B27. Total RNA from these cells were extracted and the genetic level of these cells were performed using oligonucleotide microarrays. 【Results】A twofold up-regulation of 10 genes were detected in bFGF-induced CD34^＋ cells,whereas 20 genes showed a downregulation compared with fresh-separated CD34^＋ cells. These genes were involved in stem cell specific markers,cell cycle regulators,stem cell differentiation markers and signaling pathways that are important for stem cell maintenance. 【Conclusions】bFGF can induce differentiation of human cord blood CD34^＋ cells through up-regulation or down-regulation of specifically genes. This study provides gene expression information for bFGF-induced human cord blood CD34^＋ cells and gives an improved understanding of CD34^＋ cells furthers their potential in therapeutic ap-plications.