A model of multivalent ligand-receptor equilibria which explains the effect of multivalent binding inhibitors

Quantitative relationships based on multivalent ligand receptor binding equilibria are developed which can describe the enhanced binding observed when polyvalent ligands are used as inhibitors of cell/cell interactions. This theory is able to explain the many orders of magnitude difference reported between the apparent dissociation constants determined for the interaction of Entamoeba histolytica membrane receptors with mono and multivalent N-Acetylgalactosaminide inhibitors. Given two experimentally accessible constants the theory provides a framework for the quantitative evaluation of custom designed polyvalent inhibitors of lectin and antibody mediated interactions.