Multispecific monoclonal antibodies.

Monoclonal antibodies are frequently shown to participate in unexpected cross reactions involving two apparently dissimilar antigens. This can be attributed either to partial epitope identity or to irrelevant interactions involving additional binding capacity of the antibody. The majority of such interactions appear to fall into the latter category. Such cross reactions are most commonly detected when one of the antigens has a high epitope density and the antibody is multivalent so that a spurious interaction of low intrinsic affinity is amplified by local concentration effects. In this review Souravi Ghosh and Ailsa Campbell discuss the selection of a monoclonal antibody for maximum affinity for the antigens it is designed to study and minimum cross-reactivity.