Catalytic Antibodies by Fluorescence Screening

Abstract

A series of eleven immunizations against transition-state analogs were carried out to improve the catalytic properties of Ab 9D9, a catalytic antibody that catalyzes a fluorogenic retro-Diels-Alder reaction liberating nitroxyl. By a direct fluorescence assay of cell-culture supernatant, eight new hybridoma cell lines producing catalytic antibodies for the reaction were readily identified among more than 14000 individual samples. Our results demonstrate that early catalysis screening by fluorescence allows an efficient survey of large antibody libraries, and may lead to rapid and significant improvement in catalysis.