中科院上海生命科學院/上海交大醫(yī)學院健康科學研究所研究員金穎所率干細胞研究組與上海新華醫(yī)院的陳方教授合作,，從孕婦產(chǎn)前診斷的羊水細胞中高效快速地建立了誘導多能干細胞,。
博士生李春亮等在金穎的指導下發(fā)現(xiàn)羊水細胞中一部分特殊類群（即高表達NESTIN, VIMENTIN and GATA4,不表達OCT4, SOX2, NANOG and TRA-1-60）在病毒介導的四因子誘導下，感染后第二天發(fā)生形態(tài)上的劇烈變化,，第四天出現(xiàn)人胚胎干細胞類似形態(tài)的克隆,，第六天可以機械法挑選后進行建系。經(jīng)過統(tǒng)計發(fā)現(xiàn),，AKP陽性的未分化克隆形成率最高可達到1.525%,，有趣的是，當減少因子C-MYC后,，三因子同樣可以在第四天誘導出iPS克隆,，只是AKP陽性的未分化克隆形成率稍低，從三個獨立的病人樣本中,，均能夠穩(wěn)定高效的誘導出iPS細胞,，提示這群細胞高效發(fā)生重編程具有普遍性。對建立的八株人類誘導多能干細胞進行進一步的鑒定發(fā)現(xiàn),，這些細胞能夠長期在體外穩(wěn)定傳代并保持46XX核型,，維持自我更新，蛋白和mRNA水平高表達全能性的標志基因,，如OCT4, NANOG, SOX2, SSEA4, TRA-1-60等,，AKP染色呈強陽性，甲基化PCR聯(lián)合測序法對OCT4的啟動子進行分析后發(fā)現(xiàn),，在未分化的iPS細胞和陽性對照人胚胎干細胞中,，OCT4的啟動子呈現(xiàn)低甲基化，而在供體羊水細胞和陰性對照人包皮成纖維細胞中則呈現(xiàn)高度甲基化,。STR分析結果證明這些誘導多能干細胞的確來自于對應供體的羊水細胞,，有趣的是，全基因組表達譜掃描結果提示,，研究人員所得到的羊水細胞在表達譜相關性上和人胚胎干細胞非常相似,，correlation coefficient達到0.8866，這可能是它高效被重編程的原因之一,。誘導多能干細胞的主要應用是分化和細胞移植,，研究人員嘗試了體外和體內(nèi)的分化實驗，在懸浮類胚體和實驗中,，科學家能得到典型的中,、外,、內(nèi)胚層形態(tài)細胞，RT-PCR檢測到了各個胚層標志物的表達,，定向誘導向神經(jīng)外胚層的分化中,，誘導35天后，研究人員得到了高純度的神經(jīng)前體細胞,。在體內(nèi)畸胎瘤實驗中,，注射未分化的誘導多能干細胞到免疫缺陷小鼠三個月以后能夠得到良性的畸胎瘤，切片分析能找到形態(tài)典型的肌肉,，腸管,，神經(jīng)上皮，軟骨,，肺上皮等三胚層來源組織或者細胞,，而對照細胞即起始羊水細胞注射的各組均未發(fā)現(xiàn)畸胎瘤。
綜上所述,，該項研究第一次發(fā)現(xiàn)孕婦產(chǎn)前診斷的羊水細胞中高效快速建立了誘導多能干細胞,，重編程所發(fā)生所需要的時間（6天）為人類誘導多能干細胞相關報道最短，減少了在這個過程中細胞發(fā)生變異的可能,。也為重編程的機制研究以及基于新型技術探討重編程的研究提供了理想的細胞來源,。
該成果于8月13日在線發(fā)表于國際權威雜志Human Molecular Genetics。（生物谷Bioon.com）
金穎老師參加干細胞講座
生物谷推薦原始出處：
Human Molecular Genetics, doi:10.1093/hmg/ddp386
Pluripotency can be rapidly and efficiently induced in human amniotic fluid-derived cells
Chunliang Li1,4,#, Junmei Zhou5,6,#, Guilai Shi1,4, Yu Ma1,2, Ying Yang1,4, Junjie Gu1,2, Hongyao Yu1,4, Shibo Jin1,2, Zhe Wei1,4, Fang Chen5,6 and Ying Jin1,2,3,*
1 Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences/Shanghai JiaoTong University School of Medicine; 225 South Chongqing Road, Shanghai, 200025, China 2 Shanghai Stem Cell Institute, Shanghai JiaoTong University School of Medicine, Shanghai, China 3 Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University School of Medicine, Shanghai, China 4 Graduate School of Chinese Academy of Sciences, Beijing, China 5 Department of Urology, Shanghai Children's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China 6 Tissue Engineering Laboratory, Xinhua Hospital, Shanghai Institute for Pediatric Research, Shanghai JiaoTong University School of Medicine, Shanghai, China
Direct reprogramming of human somatic cells into pluripotency has broad implications in generating patient-specific induced pluripotent stem (iPS) cells for disease modeling and cellular replacement therapies. However, the low efficiency and safety issues associated with generation of human iPS cells have limited their usage in clinical settings. Cell types can significantly influence reprogramming efficiency and kinetics. To date, human iPS cells have been obtained only from a few cell types. Here, we report for the first time rapid and efficient generation of iPS cells from human amniotic fluid-derived cells (hAFDCs) via ectopic expression of four human factors: OCT4/SOX2/KLF4/C-MYC. Significantly, typical single iPS cell colonies can be picked up six days after viral infection with high efificiency. Eight iPS cell lines have been derived. They can be continuously propagated in vitro and express pluripotency markers such as AKP, OCT4, SOX2, SSEA4, TRA-1-60 and TRA-1-81, maintaining the normal karyotype. Transgenes are completely inactivated and the endogenous OCT4 promoter is adequately demethylated in the established iPS cell lines. Moreover, various cells and tissues from all three germ layers are found in embryoid bodies and teratomas respectively. In addition, microarray analysis demonstrates a high correlation coefficient between hAFDC-iPS cells and human embryonic stem cells, but a low correlation coefficient between hAFDCs and hAFDC-iPS cells. Taken together, these data identify an ideal human somatic cell resource for rapid and efficient generation of iPS cells, allowing us to establish human iPS cells using more advanced approaches and possibly to establish disease- or patient-specific iPS cells.
