Cross Recognition and Cross Reactivity

Abstract

End products of an evolutionary process are usually singular—early drafts and tentative solutions tend to disappear once a problem has found its definitive answer. Not so with antibodies: even the simplest antigen will arouse a heterogeneous population of immunoglobulins, with firmly binding molecules at one end and indifferent ones at the other. This trivial fact has played fast and loose with detailed analysis, and it is ironic to consider that almost all we know about the structure of antibodies is derived from molecules not known to function as antibodies. Yet, the problem of heterogeneity cannot be bypassed when trying to understand how antibodies are made.