Zijlstra C, Kidson A, Schoevers E J, Daemen A J J M, Tharasanit T, Kuijk E W, Hazeleger W, Ducro-Steverink D W B, Colenbrander B, Roelen B A J
Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, Utrecht 3584 CM, The Netherlands.
Theriogenology. 2008 Oct 1;70(6):923-35. doi: 10.1016/j.theriogenology.2008.05.055. Epub 2008 Jul 9.
Embryo survival rates obtained after transfer of in vitro produced porcine blastocysts are very poor. This is probably related to poor quality of the embryos. The aim of the present study was to determine markers for good quality blastocysts. Therefore, we tried to link blastocyst morphology to several morphological and cell biological properties, and evaluated the survival of in vitro produced, morphologically classified, blastocysts following non-surgical transfer. In vitro and in vivo produced blastocysts were allocated to two groups (classes A and B) on the basis of morphological characteristics. The quality of their actin cytoskeleton, their total cell number, their ability to re-expand after cytochalasin-B treatment and the occurrence of numerical chromosome aberrations were studied and compared. In vivo produced blastocysts were used as a control. Our results indicate that the ability of blastocysts to re-expand after cytochalasin-B-induced actin depolymerization was positively correlated with the morphology of the blastocyst, and associated with the quality of the actin cytoskeleton. Chromosome analysis revealed that mosaicism is inherent to the in vitro production of porcine embryos, but also that in vivo produced blastocysts contained some non-diploid cells. In non-surgical embryo transfer experiments more recipients receiving class A blastocysts were pregnant on Day 20 than those receiving class B blastocysts. One recipient gave birth to six piglets from class A in vitro produced blastocysts, providing a verification of the enhanced viability of blastocysts that were scored as 'good' on the basis of their morphology.
体外生产的猪囊胚移植后的胚胎存活率非常低。这可能与胚胎质量差有关。本研究的目的是确定优质囊胚的标志物。因此，我们试图将囊胚形态与几种形态学和细胞生物学特性联系起来，并评估非手术移植后体外生产的、形态学分类的囊胚的存活率。根据形态学特征，将体外和体内生产的囊胚分为两组（A类和B类）。研究并比较了它们的肌动蛋白细胞骨架质量、总细胞数、细胞松弛素B处理后重新扩张的能力以及染色体数目异常的发生率。体内生产的囊胚用作对照。我们的结果表明，细胞松弛素B诱导肌动蛋白解聚后囊胚重新扩张的能力与囊胚形态呈正相关，并与肌动蛋白细胞骨架质量相关。染色体分析表明，镶嵌性是猪胚胎体外生产所固有的，但体内生产的囊胚也含有一些非二倍体细胞。在非手术胚胎移植实验中，在第20天，接受A类囊胚的受体比接受B类囊胚的受体怀孕的更多。一名受体产下了6头源自体外生产的A类囊胚的仔猪，这证实了根据形态学被评为“优质”的囊胚具有更高的活力。
