Immunochemical Localization of Integrin Subunits in the Human Placenta

Abstract

ISEMURA, M., KAZAMA, T., TAKAHASHI, K. and YAMAGUCHI, Y. Immunochemical Localization of Integrin Subunits in the Human Placenta. Tohoku J. Exp. Med., 171(2), 167-183 - Localization of integrins in the human placenta was examined in comparison with those of fibronectin and laminin. In the early chorionic villi, the α5 and β1 subunits were localized on the basal surface of villous cytotrophoblastic cells, while the α6 and β4 subunits were distributed around the entire surface of the cytotrophoblastic cells, suggesting that these cells attach to fibronectin rather than laminin on the epithelial basement membrane. In the term placenta, the α5 subunit was not detected on the epithelial cells, but the β6 and β4 subunits were detected on the basal surface of syncytiotrophoblastic cells, suggesting that these cells make use of α6 β4 integrin to attach to the trophoblastic basement membrane. These results suggest that cells utilize the specific receptor for their attachment in correspondence to the extracellular matrix component to which they attach.