一组由加州大学等多所大学共同组成的研究小组,在不使用病毒载体和基因插入的手段,通过一种安全的策略使神经干细胞经过重新编译转化为多能干细胞。这种诱导的多能干细胞(induced pluripotent stem cells,iPSCs)不但与人类胚胎干细胞极其相似,而且这些细胞还保存着供体细胞的某些功能。
这项研究发表在9月17日PLoS ONE杂志上。
通常,研究人员是利用病毒载体来产生iPSCs,并且还要考虑4个相关因素,但这种方法有时会引起细胞死亡或发生肿瘤。此外,研究人员发现,在细胞行为,基因表达以及分化为其他细胞的功能上,不论是老鼠还是人类的iPSCs,都与胚胎干细胞及其相似。目前,研究人员还未完成对iPSCs以及胚胎干细胞的全面分析。
研究人员在未使用病毒为媒介的条件下,将人类的神经干细胞转化为iPSCs,科学家发现了一些新的线索——新产生的iPSCs比人类神经干细胞在功能上更接近于胚胎干细胞,此外,该iPSCs细胞还携带着初始神经细胞的一些转录“标签”(transcriptional "signature")。(生物谷Bioon.com)
生物谷推荐原始出处:
PLoS ONE 4(9): e7076. doi:10.1371/journal.pone.0007076
Transcriptional Signature and Memory Retention of Human-Induced Pluripotent Stem Cells
Maria C. N. Marchetto1, Gene W. Yeo2, Osamu Kainohana3, Martin Marsala3, Fred H. Gage1, Alysson R. Muotri4*
1 The Salk Institute for Biological Studies, Laboratory of Genetics, La Jolla, California, United States of America, 2 University of California San Diego, School of Medicine, Department of Cellular & Molecular Medicine, Stem Cell Program, La Jolla, California, United States of America, 3 University of California, San Diego, School of Medicine, Department of Anesthesiology, La Jolla, California, United States of America, 4 University of California San Diego, School of Medicine, Department of Pediatrics/Rady Children's Hospital San Diego, Department of Cellular & Molecular Medicine, Stem Cell Program, La Jolla, California, United States of America
Genetic reprogramming of somatic cells to a pluripotent state (induced pluripotent stem cells or iPSCs) by over-expression of specific genes has been accomplished using mouse and human cells. However, it is still unclear how similar human iPSCs are to human Embryonic Stem Cells (hESCs). Here, we describe the transcriptional profile of human iPSCs generated without viral vectors or genomic insertions, revealing that these cells are in general similar to hESCs but with significant differences. For the generation of human iPSCs without viral vectors or genomic insertions, pluripotent factors Oct4 and Nanog were cloned in episomal vectors and transfected into human fetal neural progenitor cells. The transient expression of these two factors, or from Oct4 alone, resulted in efficient generation of human iPSCs. The reprogramming strategy described here revealed a potential transcriptional signature for human iPSCs yet retaining the gene expression of donor cells in human reprogrammed cells free of viral and transgene interference. Moreover, the episomal reprogramming strategy represents a safe way to generate human iPSCs for clinical purposes and basic research.