日本京都大学研究人员在新一期《细胞－干细胞》杂志网络版上发表论文说，在培育诱导多能干细胞（iPS细胞）的过程中，通过降低培养环境的氧浓度，可大幅提高细胞生成的效率。
京都大学教授山中伸弥等人在iPS细胞研究过程中，发现机体内的干细胞总是集中于氧气相对少的地方。于是，他们在利用人体皮肤细胞培养iPS细胞时把培养环境的氧浓度从通常的21％降到5％，发现iPS细胞的生成效率可提高到原来的2．5倍至4．2倍。但如果进一步降低氧浓度到1％，就会适得其反导致部分细胞死亡。研究人员又利用实验鼠的皮肤细胞培养iPS细胞，发现5％的氧浓度也是最合适的。
通过基因重新编排方法，“诱导”普通细胞回到最原始的胚胎发育状态，能够像胚胎干细胞一样进行分化，这就是所谓的iPS细胞。日本、美国等国的多个科研小组正在进行各项研究，将iPS细胞应用于新药开发和疑难疾病治疗。但iPS细胞生成效率低的问题一直没有得到解决。
山中伸弥等人认为，通过降低培养环境的氧浓度，再加上使用细胞癌变可能性较小的培养方法，就可高效地获取更高品质的iPS细胞。（生物谷Bioon.com）
生物谷推荐原始出处：
Cell Stem Cell, 27 August 2009 doi:10.1016/j.stem.2009.08.001
Hypoxia Enhances the Generation of Induced Pluripotent Stem Cells
Yoshinori Yoshida1,,,Kazutoshi Takahashi1,Keisuke Okita1,Tomoko Ichisaka2andShinya Yamanaka1,2,3,4,,
1 Center for iPS Cell Research and Application (CiRA), Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8507, Japan
2 Yamanaka iPS Cell Special Project, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
3 Department of Stem Cell Biology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
4 Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
Mouse and human somatic cells can be reprogrammed to induced pluripotent stem cells (iPSCs) by the transduction of four transcription factors, Oct 3/4, Sox2, Klf4, and c-Myc (Maherali etal., 2007,Meissner etal., 2007,Okita etal., 2007,Takahashi etal., 2007,Takahashi and Yamanaka, 2006,Wernig etal., 2007). Patient or disease-specific human iPSCs could be used for studying pathogenesis, or potentially also to treat patients suffering from incurable diseases by transplanting the regenerated grafts derived from their own cells. However, the low induction efficiency and high tumorigenesis rate due to the use of proto-oncogenes, such as c-Myc, continue to hinder the clinical application of iPS technology. Many efforts have been made to find otherfactors or small molecules that facilitate the reprogramming process (Huangfu etal., 2008,Shi etal., 2008b). In this study, we show that conducting reprogramming in hypoxic conditions results in improved efficiency for both mouse and human cells.
