Van de Velde Hilde, Cauffman Greet, Tournaye Herman, Devroey Paul, Liebaers Inge
Research Centre Reproduction and Genetics, Universitair Ziekenhuis Brussel (UZ Brussel), Laarbeeklaan 101, 1090 Brussels, Belgium.
Hum Reprod. 2008 Aug;23(8):1742-7. doi: 10.1093/humrep/den190. Epub 2008 May 24.
Early mammalian blastomeres are thought to be flexible and totipotent allowing the embryo to overcome perturbations in its organization during preimplantation development. In the past, experiments using single blastomeres from 2-, 4- and 8-cell stage mammalian embryos have provided evidence that at least some of the isolated cells can develop into healthy fertile animals and therefore are totipotent. We investigated whether isolated blastomeres of human 4-cell stage embryos could develop in vitro into blastocysts with trophectoderm (TE) and inner cell mass (ICM).
Six 4-cell stage human embryos were split and the four blastomeres were cultured individually. The expression of NANOG, a marker for ICM cells, was analysed by immunocytochemistry.
The majority of the blastomere-derived embryos followed the normal pattern of development with compaction on Day 4 and cavitation on Day 5 and developed into small blastocysts with TE and ICM on Day 6 (n = 12). The four cells of one embryo were individually capable of developing into blastocysts with TE and ICM, and NANOG was expressed in the ICM.
Although based on a small number of embryos, we conclude that the blastomeres of a 4-cell stage human embryo are flexible and able to develop into blastocysts with ICM and TE.
早期哺乳动物的卵裂球被认为具有灵活性和全能性，使胚胎能够在植入前发育过程中克服其组织结构的扰动。过去，使用2细胞、4细胞和8细胞阶段哺乳动物胚胎的单个卵裂球进行的实验提供了证据，表明至少一些分离的细胞可以发育成健康的可育动物，因此具有全能性。我们研究了人4细胞阶段胚胎的分离卵裂球是否能在体外发育成具有滋养外胚层（TE）和内细胞团（ICM）的囊胚。
将6个人4细胞阶段胚胎进行分割，4个卵裂球分别培养。通过免疫细胞化学分析ICM细胞标记物NANOG的表达。
大多数卵裂球来源的胚胎遵循正常发育模式，在第4天致密化，第5天形成囊腔，并在第6天发育成具有TE和ICM的小囊胚（n = 12）。一个胚胎的4个细胞各自能够发育成具有TE和ICM的囊胚，并且NANOG在ICM中表达。
尽管基于少量胚胎，但我们得出结论，人4细胞阶段胚胎的卵裂球具有灵活性，能够发育成具有ICM和TE的囊胚。
