A MAJOR CONTINUOUS ALLERGENIC EPITOPE OF BOVINE BETA-LACTOGLOBULIN RECOGNIZED BY HUMAN IGE BINDING

Hexapeptides of sequential overlapping sequences of beta-lactoglobulin (BLG) were used to probe serum from children with immediate-type cow milk allergy for IgE binding to continuous epitopes of BLG in an enhan ced enzyme-linked immunosorbent assay (ELISA). Six regions of IgE bind ing were identified on the BLG molecule and these were synthesized as dodecapeptides. Inhibition of IgE binding to whole BLG was used to con firm the BLG-specific binding of IgE to each of the synthesized peptid es. One of the peptides, peptide 4, showed inhibition in an IgE anti-B LG radioimmunoassay to all 16 sera tested. The patterns of inhibition with the native BLG molecule and peptide 4 were significantly correlat ed (P = 0.005), suggesting that this peptide contains a major continuo us IgE binding epitope of BLG.