Addition of GM-CSF during in vitro oocyte maturation improves embryo development and implantation and birth rate in mice

Abstract

The present study determined whether adding granulocyte–macrophage colony-stimulating factor (GM-CSF) during in vitro oocyte maturation (IVM) could improve oocyte developmental competence by examining embryo development and implantation and birth rates following embryo transfer in mice. In an initial dose-response experiment, we demonstrated that the addition of 2 and 10 ng/mL GM-CSF during IVM increased cumulus expansion (P < 0.05) but did not affect fertilisation rate compared with the control group. The addition of 10 ng/mL increased blastocyst rate (17.0%; P < 0.05) and tended to increase the number of good quality blastocysts present at 96 h of culture (+19.4%; P = 0.06) and increased blastocyst inner cell mass (+25.2%; P < 0.001), trophectoderm (+29.9%; P < 0.01), and total cell numbers (+28.6%; P < 0.05). GM-CSF also reduced the incidence of DNA damage in blastocysts in the 10 ng/mL group (−16.2%) compared with the control group. These improvements translated into increases in implantation rate (+21.0%; P < 0.05) and birth rate (+17.0%; P < 0.001) following the transfer of vitrified blastocysts. GM-CSF treatment did not alter any fetal and placental parameters. Together these results suggest that the addition of GM-CSF during IVM may improve livestock in vitro embryo production and human IVM.

Keywords

• birth rate
• gm-csf
• granulocyte–macrophage colony-stimulating factor
• implantation rate
• in vitro oocyte maturation
• ivm
• preimplantation embryo development