Menzorov Aleksei, Pristyazhnyuk Inna, Kizilova Helen, Yunusova Anastasia, Battulin Nariman, Zhelezova Antonina, Golubitsa Aleftina, Serov Oleg
Laboratory of Developmental Genetics, Institute of Cytology and Genetics SB RAS, Prospekt Lavrentyeva 10, Novosibirsk, 630090, Russia.
Department of Natural Science, Novosibirsk State University, Pirogova Str. 2, Novosibirsk, 630090, Russia.
Cytotechnology. 2016 Jan;68(1):61-71. doi: 10.1007/s10616-014-9751-y. Epub 2014 Jun 27.
Mouse embryonic stem (ES) cells are widely used in early development studies and for transgenic animal production; however, a stable karyotype is a prerequisite for their use. We derived 32 ES cell lines of outbred mice (129 × BALB (1B), C57BL × 1B, and DD × 1B F1 hybrids). Pluripotency was assessed by utilizing stem-cell-marker gene expression, teratoma formation assays and the formation of chimeras. It was shown that only 21 of the 32 ES cell lines had a diploid modal number of chromosomes of 40. In these lines, the percentage of diploid cells varied from 30.3 to 78.9 %, and trisomy of chromosomes 1, 8 and 11 was observed in some cells in 16.7, 36.7 and 20.0 % of the diploid ES cell lines, respectively. Some cells had trisomy of chromosomes 6, 9, 12, 14, 18 and 19. In situ hybridization with an X chromosome paint probe revealed that 7 of the 11 XX-cell lines had X chromosome rearrangements in some cells. Analysis of the methylation status of the Dlk1-Dio3 locus showed that imprinting was altered in 4 of the 18 ES cell lines. Thus, mouse ES cell lines are prone to chromosome abnormalities even at early passages. Therefore, routine cytogenetic and imprinting analyses are necessary for ES cell characterization.
小鼠胚胎干细胞（ES细胞）广泛应用于早期发育研究和转基因动物生产；然而，稳定的核型是其应用的前提条件。我们从远交系小鼠（129×BALB（1B）、C57BL×1B和DD×1B F1杂种）中获得了32个ES细胞系。通过利用干细胞标记基因表达、畸胎瘤形成试验和嵌合体形成来评估多能性。结果显示，32个ES细胞系中只有21个具有40条染色体的二倍体众数。在这些细胞系中，二倍体细胞的百分比在30.3%至78.9%之间，并且在16.7%、36.7%和20.0%的二倍体ES细胞系的一些细胞中分别观察到染色体1、8和11的三体性。一些细胞具有染色体6、9、12、14、18和19的三体性。用X染色体涂染探针进行原位杂交显示，11个XX细胞系中有7个在一些细胞中存在X染色体重排。对Dlk1-Dio3基因座甲基化状态的分析表明，18个ES细胞系中有4个的印记发生了改变。因此，小鼠ES细胞系即使在早期传代时也容易出现染色体异常。所以，对ES细胞进行特征鉴定时，常规的细胞遗传学和印记分析是必要的。
