据一篇发表于Oncogene杂志的研究报告，科学家首次证实羊水中的干细胞具有发育成特定细胞类型的潜能。这意味着羊水干细胞或许能够治疗某些疾病的新方法。
Anthony Atala等人发现羊膜干细胞(amnion stem cells)能够形成三维聚合体细胞——胚样小体(embryoid bodies,EBs)，而该阶段的细胞被认为可直接发育成人体所有类型的细胞。
Atala的课题组目前正在对糖尿病和肾脏疾病中评估胚样小体的治疗潜能。在2007年，该课题组曾报道在胚胎和羊水中成功分离出干细胞。
在最新发表的这项研究中，课题组通过同样的方法从羊水中获得了另外两种干细胞系。然后研究人员测试这三种干细胞系形成胚样小体的能力。通过各种独立的实验方法，研究人员证实人类羊膜干细胞确实可以发育成胚样小体。
此外，研究人员还在EBs中发现mTOR蛋白(丝氨酸/苏氨酸蛋白激酶)，该蛋白可以调节EB形成。研究人员称该蛋白的发现或许有助于了解EB形成的分子机制。（生物谷Bioon.com）
生物谷推荐原始出处：
Oncogene advance online publication 23 November 2009; doi: 10.1038/onc.2009.405
Embryoid body formation of human amniotic fluid stem cells depends on mTOR
A Valli1, M Rosner1, C Fuchs1, N Siegel1, C E Bishop2, H Dolznig1, U M?del3, W Feichtinger3, A Atala2 and M Hengstschl?ger1
1Department of Medical Genetics, Medical University of Vienna, Vienna, Austria
2Department of Urology and Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
3Wunschbabyzentrum, Lainzer Strae 6, Vienna, Austria
Human amniotic fluid stem cells (hAFSCs) harbor high proliferative capacity and high differentiation potential and do not raise the ethical concerns associated with human embryonic stem cells. The formation of three-dimensional aggregates known as embryoid bodies (EBs) is the principal step in the differentiation of pluripotent embryonic stem cells. Using c-Kit-positive hAFSC lines, we show here that these stem cells harbor the potential to form EBs. As part of the two kinase complexes, mTORC1 and mTORC2, mammalian target of rapamycin (mTOR) is the key component of an important signaling pathway, which is involved in the regulation of cell proliferation, growth, tumor development and differentiation. Blocking intracellular mTOR activity through the inhibitor rapamycin or through specific small interfering RNA approaches revealed hAFSC EB formation to depend on mTORC1 and mTORC2. These findings demonstrate hAFSCs to be a new and powerful biological system to recapitulate the three-dimensional and tissue level contexts of in vivo development and identify the mTOR pathway to be essential for this process.
