导读：英国诺丁汉大学科研人员宣布，他们开发出一种能将受精卵在人工环境下培育更长时间的设备，该设备被形象地称为“人造子宫”。
据介绍，此前的相关技术最多能将受精卵在人工环境中培育4天，然后必须移植回子宫中，不然受精卵就会死亡。而诺丁汉大学研究人员开发出一种用分子聚合物制成的装置，它能够模拟子宫中柔软的组织。用实验鼠受精卵进行的实验显示，受精卵在这个“人造子宫”中可以培育到第8天。
据报道介绍，这几天的差距在胚胎的发育中非常重要。在前4天，受精卵还只能发育到囊胚期，是一个由几十个细胞组成的小球；而在第4天至第8天，会出现一些器官发育的迹象。
在本次研究中，研究人员观察到有的细胞开始与主体分离，它们如果继续发育就会形成头部。领导研究的沙克谢夫教授说，这项成果使研究人员能够前所未有地观察胚胎发育。
他说，每个人都是从这个阶段发育过来的，如果能够通过观察胚胎发育探清器官如何形成的奥秘，将有助于再生医学上模拟再现器官形成的过程，用于治疗疾病。此外这项成果还可能有助改善人工受孕技术。
本次研究报告已发表在《自然通讯》网络杂志上。
Dynamics of anterior–posterior axis formation in the developing mouse embryo
Samantha A. Morris, Seema Grewal, Florencia Barrios, Sameer N. Patankar, Bernhard Strauss, Lee Buttery, Morgan Alexander, Kevin M. Shakesheff & Magdalena Zernicka-Goetz
The development of an anterior–posterior (AP) polarity is a crucial process that in the mouse has been very difficult to analyse, because it takes place as the embryo implants within the mother. To overcome this obstacle, we have established an in-vitro culture system that allows us to follow the step-wise development of anterior visceral endoderm (AVE), critical for establishing AP polarity. Here we use this system to show that the AVE originates in the implanting blastocyst, but that additional cells subsequently acquire AVE characteristics. These 'older' and 'younger' AVE domains coalesce as the egg cylinder emerges from the blastocyst structure. Importantly, we show that AVE migration is led by cells expressing the highest levels of AVE marker, highlighting that asymmetry within the AVE domain dictates the direction of its migration. Ablation of such leading cells prevents AVE migration, suggesting that these cells are important for correct establishment of the AP axis.
