Laboratorio de Biotecnología Animal, University of Buenos Aires, Buenos Aires, Argentina.
Theriogenology. 2013 Sep 1;80(4):357-64. doi: 10.1016/j.theriogenology.2013.04.023. Epub 2013 Jun 2.
Embryo disaggregation allows the production of two to four identical offspring from a single cow embryo. In addition, embryo complementation has become the technique of choice to demonstrate the totipotency of embryonic stem cells and induced pluripotent stem cells. Therefore, the aim of this study was to generate a new and simple method by aggregation in the well-of-the-well system to direct each single enhanced green fluorescent protein (egfp) eight-cell blastomere derived from bovine in vitro fertilization embryos to the inner cell mass (ICM) of chimeras produced with fused and asynchronic embryos. To this end, the best conditions to generate in vitro fertilization-fused embryos were determined. Then, the fused (F) and nonfused (NF) embryos were aggregated in two distinct conditions: synchronically (S), with both transgenic and F embryos produced on the same day, and asynchronically (AS), with transgenic embryos produced one day before F embryos. The highest fusion and blastocysts rates were obtained with two pulses of 40 V. The 2ASF and 2ASNF groups showed the best number of blastocysts expressing the EGFP protein (48% and 41%, respectively). Furthermore, the 2ASF group induced the highest localization rates of the egfp-expressing blastomere in the ICM (6/13, 46% of ICM transgene-expressing blastocysts). This technique will have great application for multiplication of embryos of high genetic value or transgenic embryos and also with the generation of truly bovine embryonic stem cells and induced pluripotent stem cells.
胚胎分割允许从单个牛胚胎中产生两到四个相同的后代。此外,胚胎互补已成为证明胚胎干细胞和诱导多能干细胞全能性的首选技术。因此,本研究的目的是通过在井中井系统中聚集来产生一种新的简单方法,以指导来自牛体外受精胚胎的每个单个增强型绿色荧光蛋白(egfp)八细胞胚胎分裂球向融合和异步胚胎产生的嵌合体的内细胞团(ICM)。为此,确定了生成体外受精融合胚胎的最佳条件。然后,将融合(F)和非融合(NF)胚胎在两种不同条件下聚集:同步(S),具有同一天产生的转基因和 F 胚胎,以及异步(AS),具有转基因胚胎比 F 胚胎提前一天产生。用两个 40V 的脉冲获得了最高的融合和囊胚率。2ASF 和 2ASNF 组表现出表达 EGFP 蛋白的囊胚数量最多(分别为 48%和 41%)。此外,2ASF 组诱导 egfp 表达的胚胎分裂球在 ICM 中的定位率最高(6/13,ICM 中转基因表达囊胚的 46%)。该技术将在繁殖具有高遗传价值的胚胎或转基因胚胎以及产生真正的牛胚胎干细胞和诱导多能干细胞方面具有很大的应用前景。