To examine the alteration of cellular characteristics on ploidy transition of embryonic stem (ES) cells, octaploid cells (8H1 cells) were established from tetraploid H-1 (ES) cells, and compared with tetraploid and diploid H-1 (ES) cells (4H1 and 2H1 cells, respectively). The duration of G₁, S, and G₂/M phases were essentially the same among 2H1, 4H1, and 8H1 cells, suggesting that cell cycle progression is conserved. The ratio of cell volume of 2H1, 4H1, and 8H1 cells was about 1 : 2 : 4, indicating that these polyploid cells were generated through cell cycle progression without cell division. The morphology of 8H1 cells was flagstone-like and flatter than that of 4H1 cells, and differed from the spindle-like shape of 2H1 cells, suggesting that transformation occurred during the ploidy transitions. Alkaline phosphatase activity was expressed equivalently in 2H1, 4H1, and 8H1 cells, and solid tumors that contained endodermal, mesodermal, and ectodermal cells were formed by 2H1, 4H1 or 8H1 cells after interperitoneal injection into the mouse abdomen, suggesting that pluripotency was preserved in the ploidy transition.

中文翻译：

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八倍体胚胎干细胞与四倍体和二倍体细胞的细胞周期、形态和多能性的比较。

为了检查胚胎干 (ES) 细胞倍性转变的细胞特征的改变，从四倍体 H-1 (ES) 细胞建立八倍体细胞 (8H1 细胞)，并与四倍体和二倍体 H-1 (ES) 细胞进行比较。 4H1 和 2H1 细胞）。G ₁、S 和 G ₂的持续时间/M 阶段在 2H1、4H1 和 8H1 细胞中基本相同，表明细胞周期进程是保守的。2H1、4H1和8H1细胞的细胞体积比约为1:2:4，表明这些多倍体细胞是通过细胞周期进程产生的，没有细胞分裂。8H1细胞的形态比4H1细胞呈石板状、扁平状，与2H1细胞的纺锤形不同，表明在倍性转变过程中发生了转化。碱性磷酸酶活性在 2H1、4H1 和 8H1 细胞中等量表达，腹腔注射到小鼠腹部后，2H1、4H1 或 8H1 细胞形成含有内胚层、中胚层和外胚层细胞的实体瘤，表明多能性在倍性转变。