Selection of Functional Antibodies on the Basis of Valency

Antibodies (Abs) displaying an agonist or antagonist activity are powerful tools for mimicking or blocking physiological functions in the cell. A number of applications of Abs in diagnosis and therapy require multivalent reagents, either because biological activity depends on the polymeric nature of the antigen (Ag), or because biological activity depends on an effect on the formation of homodimeric species. Often dimerization is a prerequisite for activation of a number of surface receptors by their natural ligands and divalent Abs are typically required for mimicking or blocking the activity of such ligands.