來自加州大學洛杉磯分校,，俄亥俄州立大學等處的研究人員發(fā)現(xiàn)了胚胎干細胞和皮膚細胞重新編程,，獲得胚胎狀細胞這兩者具有內源性分子區(qū)別，這首次證明了這兩種細胞類型具有明顯的不同,。這一研究成果公布在Cell Stem Cell雜志上,。

研究數(shù)據(jù)表明胚胎干細胞和重新編程獲得的細胞，后者即誘導多能干細胞,，這兩者之間雖然有重疊,，但是仍然具有明顯的基因表達差異。文章通訊作者,，Broad干細胞研究中心的Bill Lowry認為,，無論這些細胞系由何處來，用的是何種方法,，分離的是哪一種物種,，這種差別都是存在的。

2008年美國和日本的兩個科學小組同時宣布,，它們的研究人員成功地將人體皮膚細胞改造成了幾乎可以和胚胎干細胞相媲美的干細胞,。這一成果有望使胚胎干細胞研究避開一直以來面臨的倫理爭議，從而大大推動與干細胞有關的疾病療法研究,。該項研究突破分別發(fā)表在Cell和Science雜志上,。這種細胞就是iPS細胞，與胚胎干細胞相似,，具有能分化成生物體內所有組織的潛力,，但是iPS細胞并不需要破壞胚胎。

這項研究由Lowry與加州大學洛杉磯分校研究人員Kathrin Plath合作完成,，這兩位科學家都參與了加州大學首次將人類皮膚細胞重新編程為誘導多能干細胞的研究,。在這項研究中，兩位科學家利用芯片對胚胎干細胞和iPS細胞進行基因表達譜分析,，同時分析成千上萬的基因表達,，全面了解了細胞功能。

Lowry和Plath發(fā)現(xiàn),，當進行分子標簽比較的時候,，胚胎干細胞中某些基因的表達明顯與iPS細胞不同,，之后他們又將這些數(shù)據(jù)與國立健康研究院數(shù)據(jù)庫中的數(shù)據(jù)進行了比對，分析是否有其它實驗室的遺傳學數(shù)據(jù)支持他們的論點,，從中發(fā)現(xiàn)了一些重疊,，但又顯著不同的基因表達。（生物谷Bioon.com）

生物谷推薦原始出處：

Cell Stem Cell,2 July 2009 doi:10.1016/j.stem.2009.06.008

Induced Pluripotent Stem Cells and Embryonic Stem Cells Are Distinguished by Gene Expression Signatures

Mark H. Chin1,Mike J. Mason1,8,Wei Xie1,Stefano Volinia10,Mike Singer11,Cory Peterson3,Gayane Ambartsumyan2,Otaren Aimiuwu2,Laura Richter2,Jin Zhang4,Ivan Khvorostov4,Vanessa Ott11,Michael Grunstein1,Neta Lavon9,Nissim Benvenisty9,Carlo M. Croce10,Amander T. Clark2,5,6,7,Tim Baxter11,April D. Pyle3,5,6,7,Mike A. Teitell4,5,6,7,Matteo Pelegrini2,6,Kathrin Plath1,5,6,7,,andWilliam E. Lowry2,5,6,7,,

1 Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
2 Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
3 Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA 90095, USA
4 Departments of Pathology and Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
5 Broad Stem Cell Center, University of California, Los Angeles, CA 90095, USA
6 Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
7 Jonsson Comprehensive Cancer Center, University of California, Los Angeles, CA 90095, USA
8 Department of Statistics, University of California, Los Angeles, CA 90095, USA
9 Department of Genetics, Hebrew University, Jerusalem 91904, Israel
10 Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, Columbus, OH 43210, USA
11 Roche NimbleGen, Inc., Madison, WI 53719, USA

Induced pluripotent stem cells (iPSCs) outwardly appear to be indistinguishable from embryonic stem cells (ESCs). A study of gene expression profiles of mouse and human ESCs and iPSCs suggests that, while iPSCs are quite similar to their embryonic counterparts, a recurrent gene expression signature appears in iPSCs regardless of their origin or the method by which they were generated. Upon extended culture, hiPSCs adopt a gene expression profile more similar to hESCs; however, they still retain a gene expression signature unique from hESCs that extends to miRNA expression. Genome-wide data suggested that the iPSC signature gene expression differences are due to differential promoter binding by the reprogramming factors. High-resolution array profiling demonstrated that there is no common specific subkaryotypic alteration that is required for reprogramming and that reprogramming does not lead to genomic instability. Together, these data suggest that iPSCs should be considered a unique subtype of pluripotent cell.