Reproduction Abstracts

Introduction: Interspecies somatic cell nuclear transfer (iSCNT) is an useful tool to produce cloned embryos using livestock oocytes instead of the animal with peculiar reproductive system to produce endangered animal and rescue incurable disease. There are many researches about iSCNT such as porcine-bovine, mouse-porcine, mouse-bovine and so on, in contrast, canine-porcine SCNT especially have been almost no reports.

Materials and methods: Porcine fetal fibroblast (pFFs) and canine ear skin fibroblast (CES) were injected to enucleated porcine oocytes to understand why iSCNT embryos were not developed to the blastocyst stage. The development rates of embryos were investigated during culture for 7 days in porcine embryo culture medium. Gene expression levels of survivin were analyzed by quantitative real-time PCR. TUNEL analysis was conducted for arrested embryos.

Results and discussions: This study showed that iSCNT development rates and cell numbers were lower than those of SCNT and the rate of apoptotic-positive cells were significantly increased in iSCNT embryos (P< 0.05). When anti-apoptotic gene expression, survivin levels compared with SCNT and iSCNT arrested embryos were lower than normal embryos from both SCNT and iSCNT. Therefore, these findings explained the underlined mechanism why developmental arrests of SCNT and iSCNT embryos were caused at early stages.

Keywords: SCNT, interspecies, survivin, apoptosis, embryonic arrest.