The recognition pattern of sequential B cell epitopes of beta-lactoglobulin does not vary with the clinical manifestations of cow's milk allergy

Background: beta-Lactoglobulin (BLG) represents one of the major allergens causing cow's milk allergy (CMA) - a disease with a wide spectrum of clinic al symptoms. The aim of this study was to evaluate sequential B cell epitop es of BLG by the Pin-ELISA method. Furthermore, we wanted to investigate a possible association of the IgE recognition patterns in sera of patients wi th BLG sensitization and the type of clinical reactions following contact w ith cow's milk. Methods: Overlapping sequential decapeptides corresponding to the amino acid sequence of BLG were used in Pin-ELISAs specific for huma n IgE, Tested sera were from 14 individuals with CMA, 8 of them with a hist ory of immediate systemic reactions and 6 with delayed skin reactions follo wing contact with cow's milk. All of them showed specific IgE antibodies to BLG in the CAP-RAST. Control sera were from 5 healthy nonallergic individu als. Results: All sera from BLG-sensitized individuals showed IgE binding w ith one region of BLG corresponding to amino acids 95-113. Furthermore, ind ividual sera showed reactions with two further regions, 12-27 and 124-135. Inhibition of IgE binding to BLG with one soluble synthetic peptide confirm ed the major epitope. No differences were found in the B cell epitope recog nition pattern to BLG in the two groups of patients with CMA, characterized by acute systemic or delayed skin reactions. Conclusions: Using IgE Pin-EL ISAs we were able to confirm previously described sequential B cell epitope s of BLG. However, the recognition pattern of one of the major cow's milk a llergens is not predictive of the clinical type of reaction. Copyright (C) 1999 S. Karger AG, Basel.