Heparan sulfate and chondroitin sulfate proteoglycans inhibit E-selectin binding to endothelial cells

E-selectin is a cell adhesion molecule involved in the initial rolling and adhesion of leukocytes to the endothelium during inflammation. In addition, in vitro studies have suggested that an interaction between E-selectin and binding sites such as sialyl Lewis X-containing oligosaccharides on endoth elial cells may be important for angiogenesis. In order to investigate the binding of E-selectin to endothelial cells, we developed an ELISA assay usi ng chimeric E-selectin-Ig molecules and endothelial cells fixed on poly-L-l ysine coated plates. Our results indicate that E-selectin-Ig binds to both bovine capillary endothelial cells and human dermal microvascular endotheli al cells in a calcium-dependent and saturable manner. The binding is inhibi ted markedly by heparin and by syndecan-1 ectodomain, and moderately by cho ndroitin sulfate, but not by sialyl Lewis X-containing oligosaccharides. Th ese results suggest that heparan sulfate and chondroitin sulfate proteoglyc ans on endothelial cells are potential ligands for E-selectin. J. Cell. Bio chem. 80:522-531, 2001. (C) 2001 Wiley-Liss, Inc.