Masaki Hideki, Ishikawa Tetsuya, Takahashi Shunichi, Okumura Masafumi, Sakai Noriko, Haga Megumi, Kominami Katsuya, Migita Hideyuki, McDonald Fiona, Shimada Fumiki, Sakurada Kazuhiro
Department of Stem-Cell-Based Drug Discovery, Research Center Kobe, Bayer Yakuhin Ltd., Kobe, Hyogo, Japan.
Stem Cell Res. 2007 Nov;1(2):105-15. doi: 10.1016/j.scr.2008.01.001. Epub 2008 Jan 31.
Induction of pluripotent stem cells from human fibroblasts has been achieved by the ectopic expression of two different sets of four genes. However, the mechanism of the pluripotent stem cell induction has not been elucidated. Here we identified a marked heterogeneity in colonies generated by the four-gene (Oct3/4, Sox2, c-Myc, and Klf4) transduction method in human neonatal skin-derived cells. The four-gene transduction gave a higher probability of induction for archetypal pluripotent stem cell marker genes (Nanog, TDGF, and Dnmt3b) than for marker genes that are less specific for pluripotent stem cells (CYP26A1 and TERT) in primary induction culture. This tendency may reflect the molecular mechanism underlying the induction of human skin-derived cells into pluripotent stem cells. Among the colonies induced by the four-gene transduction, small cells with a high nucleus-to-cytoplasm ratio could be established by repeated cloning. Subsequently established cell lines were similar to human embryonic stem cells as well as human induced pluripotent stem (iPS) cells derived from adult tissue in morphology, gene expression, long-term self-renewal ability, and teratoma formation. Genome-wide single-nucleotide polymorphism array analysis of the human iPS cell line indicates that the induction process did not induce DNA mutation.
通过异位表达两组不同的四个基因，已实现从人成纤维细胞诱导多能干细胞。然而，多能干细胞诱导的机制尚未阐明。在这里，我们在人新生儿皮肤来源的细胞中，鉴定出通过四基因（Oct3/4、Sox2、c-Myc和Klf4）转导方法产生的集落存在明显的异质性。在原代诱导培养中，四基因转导对原型多能干细胞标记基因（Nanog、TDGF和Dnmt3b）的诱导概率高于对多能干细胞特异性较低的标记基因（CYP26A1和TERT）。这种趋势可能反映了人皮肤来源的细胞诱导为多能干细胞的分子机制。在四基因转导诱导的集落中，通过反复克隆可以建立核质比高的小细胞。随后建立的细胞系在形态、基因表达、长期自我更新能力和畸胎瘤形成方面，与人类胚胎干细胞以及源自成人组织的人类诱导多能干细胞（iPS）相似。对这个人iPS细胞系的全基因组单核苷酸多态性阵列分析表明，诱导过程未诱导DNA突变。
