IMMUNOHISTOCHEMICAL ANALYSIS OF INSULIN-LIKE GROWTH FACTOR-BINDING PROTEIN-1, PROTEIN-2, AND PROTEIN-3 IN IMPLANTATION SITES OF THE MOUSE

Purpose: Our purpose was to analyze potential interactions between the embryo and the maternal endometrial interface in vivo by analyzing im munolocalization of insulin-like growth factor-binding proteins (IGFBP s) -1, -2, and -3 in implantation sites of the mouse. Methods: Six-wee k-old B6D2F1 female mice underwent superovulation followed by mating a nd sacrifice at timed intervals. Formalin-fixed paraffin-embedded tiss ue was used for avidin-biotin immunocytochemical localization of IGFBP s utilizing standard methodology. Results: Immunostaining at 1.5 days post coitum revealed light staining in the epithelial glandular cells and faint staining in decidual stroma for both IGFBP-1 and IGFBP-2. At 7.5-10.5 days post coitum, there was moderate-dense immunostaining in the decidualized stromal cells at the implantation site for all three IGFBPs, whereas light immunostaining was seen in nonimplantation site decidua. Conclusions: Compartmentalization of immunostaining for IGFB P-1, -2, and -3 within decidualized stroma suggests that these protein s may be regulated by trophoblastic and/ or embryonic signals.