Diabetes Transplant Unit, Prince of Wales Hospital & The University of New South Wales, Australia.
Pancreas. 2012 Jan;41(1):54-64. doi: 10.1097/MPA.0b013e31822362e4.
A challenge in using human embryonic stem cells (hESCs) as the source of surrogate β cells is the establishment of methods that could effectively direct their differentiation into functional β cells. The aim of this study was to assess the effect of NANOG gene suppression in differentiating hESCs as a mean of increasing the efficiency with which endoderm-derived pancreatic cells could be generated.
A homogenous cell population with stable suppression of NANOG was generated in hESC ENVY line using plasmid-based siRNA approach. Pancreatic differentiation was undertaken according to the ontology-based in vitro selection protocol and followed by transplantation into immunodeficiency mice to mature in vivo.
We observed up-regulation of definitive endoderm genes, which expand the role of NANOG in blocking definitive endoderm differentiation. The ontology-based differentiation protocol resulted in increased expression of markers essential for pancreatic epithelium development. Transplantation of these cells further revealed a homogenous pancreatic exocrine-like morphology that stained positively for amylase.
The suppression of NANOG displayed an effective differentiation toward endoderm and pancreatic progenitors. Investigation of the factors required for endocrine formation combined with a prolonged in vivo culturing could be further used to increase the ratio of endocrine-exocrine cells fate.
以人类胚胎干细胞(hESC)作为替代β细胞的来源存在一个挑战,即建立能够有效指导其分化为功能性β细胞的方法。本研究旨在评估抑制 NANOG 基因在诱导 hESC 内胚层分化为胰腺细胞中的作用,以提高内胚层来源的胰腺细胞生成效率。
使用基于质粒的 siRNA 方法,在 hESC ENVY 系中生成具有稳定 NANOG 抑制作用的同质细胞群体。根据基于本体论的体外选择方案进行胰腺分化,然后移植到免疫缺陷小鼠体内进行体内成熟。
我们观察到明确内胚层基因的上调,这扩展了 NANOG 在阻止明确内胚层分化中的作用。基于本体论的分化方案导致与胰腺上皮发育相关的标志物的表达增加。这些细胞的移植进一步显示出一种均匀的胰腺外分泌样形态,对淀粉酶呈阳性染色。
NANOG 的抑制作用显示出向内胚层和胰腺祖细胞的有效分化。结合体内延长培养进一步研究内分泌形成所需的因素,可以进一步提高内分泌-外分泌细胞命运的比例。