Analysis of transgenic rabbit vitrified embryos carrying EGFP geney

Abstract

The aim of our study was to investigate influence of vitrification on developmental rate and quality (total cells number, number of ICM blastomeres, apoptotic index and embryo diameter) of rabbit transgenic embryos carrying exogenous EGFP gene. EGFPpositive rabbit embryos were produced under in vitro conditions by the microinjection of foreign gene into the pronucleus of fertilized eggs. EGFP expression was detected by fluorescent microscope (at 492 nm). Developmental rate of vitrified/thawed transgenic embryos reached hatching blastocyst stage (68.00 %) differed significantly (p<0.001) from those in control embryos (100.00 % resp.). The higher proportion of ICM cells (32.00 %) and embryo diameter (130.85 ± 10.90) were found in the control group compared to transgenic ones. The ratio of apoptotic cells was higher (2.90 %) in vitrified EGFP-positive embryos compared with the control group (2.50 %). Our results demonstrate, that neither gene microinjection itself, nor exogenous (EGFP) gene expression do interfere with quality of rabbit embryos. However, combination of microinjection and vitrification significantly decreases (p <0.001) survival rate of rabbit embryos.