Effect of fibronectin and leukaemia inhibitory factor on matrix metalloproteinases in mouse blastocyst

This study was designed to detect the effects of fibronectin (FN) and leukaemia inhibitory factor (LIF) on matrix metallopoteinases (MMPs) of mouse blastocysts. The experiments comprised four groups: first, blastocysts grew on the dishes with FN-coated; the second, without FN-coated; the third group, without FN coated, but with 20 ng/muL LIF added to culture medium; and the fourth group, with both FN-coated and 20 ng/muL LIF added. Using MMP-2 and MMP-9 primers respectively, the expressions of MMP-2 and MMP-9 were detected by RT-PCR and cloning identification. The results showed that in the first group, MMP-2 and MMP-9 were produced after 12 and 24 h culturing; in the third group, there were both MMP-2 and MMP-9 bands when blastocysts were cultured for 24 h; and in the fourth group, MMP-2 and MMP-9 bands appeared when blastocysts were cultured for 6, 12 and 24 h. But in the second group no MMP-2 or MMP-9 band appeared. These results show that FN may initiate the transcription of MMP-2 and MMP-9 genes to mRNA through signal transduction pathway mediated by integrin receptor and LIF may promote the expression of MMPs mRNA, which guaranteed the accuracy of embryo implantation by associating the invasive blastocysts with the receptive endometrium.