Science新闻：革命性重编程论文面临撤稿

　　

生物通报道：一月二十九日Nature上发表了的两篇文章，报道了一个异常简单的多能干细胞制造方法。这一技术发表后不久就引起了广泛的争议，现在文章的共同作者之一提出，应暂时撤回这两篇文章，对实验中的数据和图片进行进一步验证。

现在人们主要通过两种途径，将已分化的成体细胞重编程为干细胞状态：核移植和诱导多能基因表达（iPS技术）。

这项新研究介绍了一种被称为STAP（stimulus-triggered acquisition of pluripotency）的革命性细胞重编程技术。文章指出，将成体细胞暴露在压力条件下（例如酸性环境或机械力），能够促使它们获得类似胚胎细胞的多能性。人们可以诱导这些细胞分化成为机体中任何类型的细胞。

这两篇文章一经发表就引起了激烈的争论，批评者们指出文章中的一些图片存在问题，与第一作者Haruko Obokata其他文章中用过的图片非常相似。Haruko Obokata是日本理化研究所发育生物学研究中心（RIKEN Center for Developmental Biology）的研究小组带头人。

二月十三日RIKEN宣布对这一事件进行调查。几天后，批评者们又在文章中发现了更多有问题的图片，这些图片很像Obokata2011年博士论文中用过的图片。

据华尔街日报和NHK今天报道，这两篇文章的共同作者之一，Yamanashi大学的克隆研究者Teruhiko Wakayama宣布，尽管他还未完全放弃这两篇文章，但他已经对它们丧失了信心。

“总得来说，有太多不清楚的因素，”Wakayama说。“在某种程度上，我已经丧失了对文章的信心。我认为最好是暂时撤回文章，以便进行深入核查。等到具备了准确的数据和图片之后，再发表有把握的研究结果。”

Wakayama还指出，RIKEN的调查结果应该公开，以便澄清到底哪里出了问题。据NHK报道，RIKEN拒绝对此发表评论。

目前世界上许多科学家们都在尝试重复这一技术，但迄今未至还没有人公开表示获得了成功。三月五日，RIKEN发布了更多构建STAP细胞的详细步骤。

干细胞研究者Paul Knoepfler在自己的博客上紧跟事态的进展，包括公布科学家们重复这项研究的结果。在他最近的网上调查中，53%的人表示“基本确信STAP细胞不真实”。二月二十七日Wakayama曾在一次采访中呼吁人们“等待至少一年”，看看这一技术是否可以重复。（相关报道：Nature头条，重大突破细胞重编程新技术）

 

生物通编辑：叶予

生物通推荐论文摘要：

Stimulus-triggered fate conversion of somatic cells into pluripotency

Here we report a unique cellular reprogramming phenomenon, called stimulus-triggered acquisition of pluripotency (STAP), which requires neither nuclear transfer nor the introduction of transcription factors. In STAP, strong external stimuli such as a transient low-pH stressor reprogrammed mammalian somatic cells, resulting in the generation of pluripotent cells. Through real-time imaging of STAP cells derived from purified lymphocytes, as well as gene rearrangement analysis, we found that committed somatic cells give rise to STAP cells by reprogramming rather than selection. STAP cells showed a substantial decrease in DNA methylation in the regulatory regions of pluripotency marker genes. Blastocyst injection showed that STAP cells efficiently contribute to chimaeric embryos and to offspring via germline transmission. We also demonstrate the derivation of robustly expandable pluripotent cell lines from STAP cells. Thus, our findings indicate that epigenetic fate determination of mammalian cells can be markedly converted in a context-dependent manner by strong environmental cues.

Bidirectional developmental potential in reprogrammed cells with acquired pluripotency

We recently discovered an unexpected phenomenon of somatic cell reprogramming into pluripotent cells by exposure to sublethal stimuli, which we call stimulus-triggered acquisition of pluripotency (STAP)1. This reprogramming does not require nuclear transfer2, 3 or genetic manipulation4. Here we report that reprogrammed STAP cells, unlike embryonic stem (ES) cells, can contribute to both embryonic and placental tissues, as seen in a blastocyst injection assay. Mouse STAP cells lose the ability to contribute to the placenta as well as trophoblast marker expression on converting into ES-like stem cells by treatment with adrenocorticotropic hormone (ACTH) and leukaemia inhibitory factor (LIF). In contrast, when cultured with Fgf4, STAP cells give rise to proliferative stem cells with enhanced trophoblastic characteristics. Notably, unlike conventional trophoblast stem cells, the Fgf4-induced stem cells from STAP cells contribute to both embryonic and placental tissues in vivo and transform into ES-like cells when cultured with LIF-containing medium. Taken together, the developmental potential of STAP cells, shown by chimaera formation and in vitro cell conversion, indicates that they represent a unique state of pluripotency.