Glycodelin: A pane in the implantation window

Glycodelin is an endometrial protein with proposed immunomodulatory activit y during human embryonic nidation. In this review we describe the effects o f ovarian hormones on glycodelin transcription, synthesis, and secretion by human epithelial cells and focus on the importance of glycodelin in implan tation. We demonstrate that glycodelin transcription, synthesis, and secret ion by human epithelial cells are stimulated by progestins and antiprogesti ns but not by estrogen. Sequences localized within a 403-base-pair region-f lanking the 5' human glycodelin gene promoter appear to be responsible for transcriptional activation of this gene mediated by progesterone receptor-l igand complexes. Relaxin, purported to enhance glycodelin production in viv o and in prior in vitro studies, had no stimulatory effect on the expressio n of this gene in vitro in our models.