美国洛克菲勒大学Ali H. Brivanlou，Eric D. Siggia和Mijo Simunovic共同合作取得一项新突破。他们提出了一种装配体方法，通过将人类胚胎干细胞 (hESC) 衍生的极化上皮细胞与直接分化产生的人类胚胎干细胞衍生的胚胎外组织共培养，对附着后人类胚胎进行建模，从而模拟体外附着和前后对称性破坏。相关论文2022年6月2日在线发表于《细胞—干细胞》杂志上。

在这里，研究人员提出了一种通过组装预先形成的极化上皮外胚层和胚胎外细胞，来模拟附着后人类胚胎的策略，使它们能够自我组织成一个模仿培养皿附着人类胚胎的结构。该模型在体外附着，并且在没有外源性形态发生素的情况下，打破了前后对称性，从而产生了早期原肠胚形成细胞类型。他们的组装方法能够以模块化的方式升级或交换胚胎外组织，以进入更高级阶段的附着后发育，同时遵守道德政策。

据介绍，科学家对人类胚胎着床和原肠形成的分子机制缺乏了解，这主要是由于人类胚胎实验的技术和伦理限制。已经报道了人类胚胎的替代品，其中胚胎干细胞的3D簇以逐步分化的方式来模拟人类胚胎发生的各个方面。然而，对附着以后的胚胎发生事件进行建模仍然具有挑战性。

附：英文原文

Title: In vitro attachment and symmetry breaking of a human embryo model assembled from primed embryonic stem cells

Author: Mijo Simunovic, Eric D. Siggia, Ali H. Brivanlou

Issue&Volume: 2022/06/02

Abstract: Our knowledge of the molecular mechanisms surrounding human embryo implantation and gastrulation is lacking, largely due to technical and ethical limitations of experimenting with human embryos. Alternatives to human embryos have been reported, in which 3D clusters of embryonic stem cells are differentiated in a stepwise manner to model aspects of human embryogenesis. Yet it remains challenging to model the events past attachment. We propose a strategy of modeling the post-attachment human embryo by assembling a pre-formed polarized epithelial epiblast and extraembryonic cells, allowing them to self-organize into a structure that mimics the dish-attached human embryo. The model attaches in vitro and, in the absence of exogenous morphogens, breaks anteroposterior symmetry, giving rise to early gastrulation cell types. Our assembloid approach enables in a modular way to upgrade or exchange extraembryonic tissues to access more advanced stages of post-attachment development while complying with ethical policies.

DOI: 10.1016/j.stem.2022.05.001

Source: https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(22)00201-6