Epitope mapping studies of broad specificity monoclonal antibodies to cereal prolamins

The characterisation of three monoclonal antibodies (Mabs), two raised against a glutenin fraction of wheat storage protein and a third raised against a synthetic peptide conjugate, is described. The three Mabs exhibited broad reactivity as shown by ELISA and immunoblotting. The amino acid sequences constituting the epitopes recognised by each Mab were determined using immobilised pin-bound peptides and were confirmed by using competitive ELISAs with synthesised peptides. By matching the predicted epitopes with published sequences for a number of cereal storage proteins the degree of reactivity of the Mabs was correlated with the frequency with which these epitopes occur. It was possible, therefore, to show that the observed broad reactivity of the antibodies was a function not of the antibodies (which were highly specific) but resulted from structural homology of the gluten proteins.