今天一条很大的新闻 日本与美国两个研究团队同时在今天发表一项研究成果 表示只要在一般人的皮肤细胞中入四个基因後 即可将该皮肤细胞转为干细胞 不但外观型态与干细胞无异 此一转型後的干细胞也能分化成不同的细胞 此项技术将会为干细胞研究与很多疾病治疗的研究带来重大的突破 新闻如下 http://sciencenow.sciencemag.org/cgi/content/full/2007/1120/1 Researchers Turn Skin Cells Into Stem Cells By Gretchen Vogel ScienceNOW Daily News 20 November 2007 Scientists have managed to reprogram human skin cells directly into cells that look and act like embryonic stem (ES) cells. The technique makes it possible to generate patient-specific stem cells to study or treat disease without using embryos or oocytes--and therefore could bypass the ethical debates that have plagued the field. "This is like an earthquake for both the science and politics of stem cell research," says Jesse Reynolds, policy analyst for the Center for Genetics and Society in Oakland, California. The work builds on a study published last year by Shinya Yamanaka of Kyoto University in Japan, which showed that mouse tail cells could be transformed into ES-like cells by inserting four genes (ScienceNOW, 3 July 2006). Those genes are normally switched off after embryonic cells differentiate into the various cell types. In June this year, Yamanaka and another group reported that the cells were truly pluripotent, meaning that they had the potential to grow into any tissue in the body (ScienceNOW, 6 June). Now the race to repeat the feat in human cells has ended in a tie: Two groups report today that they have reprogrammed human skin cells into so-called induced pluripotent cells (iPCs). In a paper published online in Cell, Yamanaka and his colleagues show that their mouse technique works with human cells as well. And in a paper published online in Science, James Thomson of the University of Wisconsin, Madison, and his colleagues report success in reprogramming human cells, again by inserting just four genes, two of which are different from those Yamanaka uses. In the new work, Yamanaka and his colleagues used a retrovirus to ferry into adult cells the same four genes they had previously used to reprogram mouse cells: OCT3/4, SOX2, KLF4, and c-MYC. They reprogrammed cells taken from the facial skin of a 36-year-old woman and from connective tissue from a 69-year-old man. Roughly one iPC cell line was produced for every 5000 cells the researchers treated using the technique, an efficiency that enabled them to produce several cell lines from each experiment. Thomson's team started from scratch, identifying its own list of 14 candidate reprogramming genes. Like Yamanaka's group, the team used a systematic process of elimination to identify four factors: OCT3 and SOX2, as Yamanaka used, and two different genes, NANOG and LIN28. The group reprogrammed cells from fetal skin and from the foreskin of a newborn boy. The researchers were able to transform about one in 10,000 cells, less than Yamanaka's technique achieved, Thomson says, but still enough to create several cell lines from a single experiment. [下略] --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 128.223.138.98 ※ senlin:转录至看板 Biotech 11/21 07:27