Differential expression of insulin-like growth factors in the uterine epithelium and extracellular matrix during early pregnancy
Slater, M.; Murphy, C.R.
Matrix Biology Journal of the International Society for Matrix Biology 18(6): 579-584
ISSN/ISBN: 0945-053X PMID: 10607919 DOI: 10.1016/s0945-053x(99)00051-7
We have studied the simultaneous expression of insulin-like growth factor I (IGF-I) and insulin-like growth factor II (IGF-II) in the uterine epithelium and extracellular matrix during the time of trophoblast attachment and implantation. These studies reveal that IGF-I and IGF-II display different spatial and temporal patterns of expression during early pregnancy, and suggest a role for them in the process of attachment and implantation. Specifically, IGF-I is strongly expressed in the basal lamina which is the site of trophoblast invasion into the maternal stroma, and also in the apical epithelium, the site of initial trophoblast attachment. IGF-II is expressed to a lesser extent in the basal lamina, lateral plasma membranes and apical epithelium on day 3 but is only prominent apically at the time of implantation, suggesting a role in attachment.