Functional mimicry: elicitation of a monoclonal anti-idiotypic antibody hydrolizing beta-lactams

Antigen mimicry by anti-idiotypic antibodies is investigated as a reliable strategy to achieve molecular imprinting of an enzymatic activity. A monoclonal anti-idiotypic antibody (Ab2-9G4H9) was elicited by using a monoclonal antibody (Ab1-7AF9) specific for the beta-lactamase active site. Catalytic features of Ab2 were characterized with beta-lactamase substrates. The antibody combining site appeared to have retained a part of the catalytic specificity. The relevance of the idiotypic mimicry concept for the generation of catalytic antibodies was further demonstrated by eliciting a third generation antibody (Ab3), which was shown to recognize beta-lactamase: the complete internal image properties of Ab2 9G4H9, including binding and catalytic properties, were thus checked.