Hirata Shuji, Fukasawa Hiroko, Wakayama Sayaka, Wakayama Teruhiko, Hoshi Kazuhiko
Department of Obstetrics and Gynecology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo, Yamanashi, Japan.
Cell Reprogram. 2011 Feb;13(1):7-11. doi: 10.1089/cell.2010.0059. Epub 2010 Oct 21.
The successful generation of cloned animals and the establishment of embryonic stem (ES) cell lines from somatic cells suggest that these techniques may be used in human regenerative medicine. However, the fact that oocytes must be donated by women undergoing infertility treatment remains a fundamental ethical objection, as they might be concerned about the potential exploitation of their genome. Here, we investigated the reprogramming potential of enucleated and cryopreserved oocytes for the development of full-term cloned mice. BDF1 strain mouse oocytes were cryopreserved at metaphase II, before and after enucleation. After thawing, cumulus cell nuclei were microinjected to generate clones. Although the rate of development of cloned embryos to the blastocyst stage using the treated oocytes was lower than that obtained using fresh oocytes, three live pups were delivered after embryo transfer into pseudopregnant females (0.4% of the oocytes used). Thus, although cryopreservation reduces the potential of oocytes, these cells retain the ability to support the full-term development of cloned embryos. In addition, the removal of DNA from human oocytes may alleviate the ethical and psychological problems for women who are undergoing infertility treatment and are considering oocyte donation for research or therapeutic purposes.
克隆动物的成功培育以及从体细胞建立胚胎干细胞（ES）系表明，这些技术可能会用于人类再生医学。然而，卵母细胞必须由接受不孕症治疗的女性捐赠这一事实仍然是一个根本性的伦理问题，因为她们可能担心自己的基因组会被潜在利用。在此，我们研究了去核和冷冻保存的卵母细胞对足月克隆小鼠发育的重编程潜力。将BDF1品系小鼠卵母细胞在去核前后的中期II进行冷冻保存。解冻后，显微注射卵丘细胞核以产生克隆体。尽管使用处理过的卵母细胞的克隆胚胎发育到囊胚阶段的比率低于使用新鲜卵母细胞获得的比率，但将胚胎移植到假孕雌性体内后产下了三只活体幼崽（占所用卵母细胞的0.4%）。因此，尽管冷冻保存降低了卵母细胞的潜力，但这些细胞仍保留支持克隆胚胎足月发育的能力。此外，从人类卵母细胞中去除DNA可能会减轻正在接受不孕症治疗并考虑为研究或治疗目的捐赠卵母细胞的女性的伦理和心理问题。
