Alteration of the timing of implantation by in vivo gene transfer: delay of implantation by suppression of nuclear factor kappaB activity and partial rescue by leukemia inhibitory factor.

Nuclear factor kappaB (NF-kappaB) is activated in the murine endometrium during implantation period [Am. J. Reprod. Immunol. 51 (2004) 16]. Transient transfection of IkappaBalpha mutant (IkappaBalphaM) cDNA into the mouse uterine cavity using hemagglutinating virus of Japan envelope vector suppressed uterine NF-kappaB activity less than half of that observed in control on days 3.5 and 4.5 p.c. IkappaBalphaM cDNA transfection led to significant delay of implantation. After IkappaBalphaM cDNA transfection, LIF mRNA expression in the uterus was significantly suppressed on days 3.5 and 4.5 p.c. Co-transfection of LIF cDNA with IkappaBalphaM cDNA in the uterus partially rescued the delay of implantation induced by suppression of NF-kappaB activity. Taken together, these findings indicate that NF-kappaB activation determines the timing of the implantation, at least in part, via control of LIF expression.