Leukaemia inhibitory factor increases αvβ3 integrin expression in cultured mouse blastocysts

Abstract

Blocking leukaemia inhibitory factor (LIF) has a negative effect on the implantation of mouse embryos. It has been determined that LIF regulates the expression of endometrial αvβ3 integrin, but its role in trophoblast cells remains unclear. The aim of this study was to evaluate the effect of 1000 units mL−1 LIF on the expression of LIF receptor alpha (Lifr), integrin alpha V (Itgav), integrin beta 3 (Itgb3) and some apoptosis-related genes in blastocysts formed from 8-cell mouse embryos. Embryos obtained from superovulated NMRI mice were divided into four groups and cultured to the blastocyst stage. Groups 1 and 2 were simple embryo cultures in the absence and presence of LIF respectively; Groups 3 and 4 were embryo cocultures in the absence and presence of LIF respectively. The number of cells in blastocysts was counted and the expression of Itgav, Itgb3 and some apoptosis-related genes was determined using real-time polymerase chain reaction. The blastocyst rate, cell count, survival rate and expression of the Itgav and Itgb3 genes were significantly higher in the coculture groups and in the simple culture group with LIF than in the simple culture group without LIF. In conclusion, LIF improves the growth and cell count of blastocysts, increases the expression of the Itgav and Itgb3 genes in blastocysts and plays an important role in the success of implantation.