Use of frozen-thawed oocytes for efficient production of normal offspring from cryopreserved mouse spermatozoa showing low fertility.
Use of frozen-thawed oocytes for efficient production of normal offspring from cryopreserved mouse spermatozoa showing low fertility.
复制标题
DOI：
--
复制
发表时间：
2005-04
影响因子：
0.8
通讯作者：
Wataru Sakamoto;T. Kaneko;N. Nakagata
中科院分区：
文献类型：
--
作者：
Wataru Sakamoto;T. Kaneko;N. Nakagata
冷冻精子和未受精卵母细胞是保存小鼠遗传资源的有效手段。然而，冷冻解冻的卵母细胞与精子在体外受精的比例很低，因为精子，特别是冷冻解冻的精子，由于皮质颗粒过早释放后透明带硬化，不能渗透到卵母细胞中。为了使冷冻保存的转基因小鼠配子有效地产生后代，我们采用卵胞浆内单精子注射（ICSI）方法使冷冻解冻的配子受精，并评估胚胎植入前和植入后的发育情况。与新鲜的未受精卵母细胞相比，冷冻解冻的未受精卵母细胞对注射损伤的耐受性强，注射冷冻精子后的存活率分别为51%和78%。精子注射后存活的冷冻解冻卵母细胞正常发育到囊胚期并产生后代。此外，通过ICSI受精的冷冻配子也可获得转基因后代。这些结果表明，ICSI是一种从低生育能力的转基因精子中产生后代的有效技术，并且使用冷冻解冻的卵母细胞可以保护遗传资源，因为保存不佳的配子不会浪费。
Freezing of spermatozoa and unfertilized oocytes is a useful tool for the conservation of mouse genetic resources. However, the proportion of frozen-thawed oocytes fertilized with spermatozoa in vitro is low because spermatozoa, especially those frozen-thawed, can not penetrate into oocytes because of hardening of the zona pellucida following premature release of cortical granules. To produce offspring efficiently from cryopreserved transgenic mouse gametes, we fertilized frozen-thawed gametes by using intracytoplasmic sperm injection (ICSI) and assessed pre- and postimplantation development of embryos. Compared with fresh unfertilized oocytes, frozen-thawed unfertilized oocytes were highly tolerant to damage by injection, as the survival rates after injection of frozen spermatozoa were 51 and 78%, respectively. Frozen-thawed oocytes that survived after sperm injection developed normally to the blastocyst stage and gave rise to offspring. Moreover, offspring with transgenes also were obtained from frozen gametes fertilized by ICSI. These results demonstrate that ICSI is an efficient technique for producing offspring from transgenic spermatozoa showing low fertility and that use of frozen-thawed oocytes leads to conservation of genetic resources because suboptimally preserved gametes are not wasted.