A CRUCIAL EFFECT OF LIGAND CLUSTERING ON THE INHIBITION OF BINDING BYL-SELECTIN IN INTERCELLULAR-ADHESION

Glucan sulfates were found to be potent ligands for L-selectin by a qu antitative liquid phase analysis system (Yoshida, T. et al., fur. J. B iochem., in press). The affinity of glucan sulfates to L-selectin-IgG chimera was dependent on the size of the glucan sulfates as well as on the inter-glucose linkages. In the current report, these glucan sulfa tes are shown to inhibit the interaction of an endothelial cell line w ith lymphocytes. The effect of ligand size appears to be more remarkab le in the cell-cell binding than in the liquid phase analysis. The aff inity of amylose sulfate continues to increase, as their size increase s even beyond 12 kDa, at which its affinity reached a plateaux in the liquid phase analysis. (C) 1994 Academic Press, Inc.