Bivalent hapten-antibody interactions—II. Bivalent haptens as probes of combining site depth

Abstract

Carson and Metzger (1974)have shown that Fab′ fragments form dimer with bivalent hapten. The amounts of dimer formed with the fragments was similar to the amount formed with intact antibody and the same bivalent hapten. They concluded that the lenght of the bivalent hapten was a measure of combining site depth. In this communication, we extend these observations of Carson and Metzger by using a homologous series of bivalent haptens to study intact antibody molecules, F(ab′) 2 fragments, and Fab′ fragments. The results of these studies are consistent with the conclusions of Carson and Metzger, and the data enable us to construct a plot of the distribution of antibody dimers as a function of the chain length of the cross-linking bivalent hapten.