Effect of bovine oviductal epithelial cell lysate on the developmental competence and quality of bovine in vitro fertilized embryos

Abstract

In vitro fertilization (IVF) technology for embryo production has been applied in basic research, animal husbandry and medicine. However, the developmental efficiency and quality of embryos produced by IVF are inferior to those produced in vivo. In this study, we investigated the effects of supplementing bovine oviductal epithelial cells (BOEC) lysate during the in vitro culture period on the developmental competence and quality of bovine embryos. IVF embryos were cultured for 4 days post-IVF in medium supplemented with 10 % BOEC lysate at various concentrations (1.0 × 10⁵, 2.0 × 10⁵, and 4.0 × 10⁵ cells/mL) or 10 % PBS (−), which was used to adjust the lysate concentration (control). BOEC lysate at 2.0 × 10⁵ cells/mL significantly increased the blastocyst formation rate compared to that in the control group. Blastocysts from BOEC lysate supplemented groups showed significantly lower apoptosis rate than that in the control group. The ratio of inner cell mass cell number in blastocysts was significantly higher in all BOEC lysate supplemented groups than in the control group. The survival rate after vitrification/thawing was improved in the 1.0 × 10⁵ and 2.0 × 10⁵ cells/mL BOEC lysate supplemented groups. In addition, gene expression analysis of blastocysts showed that 2.0 × 10⁵ cells/mL of BOEC lysate supplementation significantly enhanced the expression of anti-apoptotic genes (BCL2 and BIRC5), antioxidant-related genes (GPX1 and SOD2), and cell differentiation-related genes (SOX2 and OCT4). In conclusion, supplementation with 2.0 × 10⁵ cells/mL BOEC lysate during early in vitro culture improved the developmental competence and quality of bovine IVF embryos.