title: Mapping of conformational IgE epitopes with peptide-specific monoclonal antibodies reveals simultaneous binding of different IgE antibodies to a surface patch on the major birch pollen allergen, Bet v 1.
abstract: Allergic inflammation is based on the cross-linking of mast cell and basophil-bound IgE Abs and requires at least two binding sites for IgE on allergens, which are difficult to characterize because they are often conformational in nature. We studied the IgE recognition of birch pollen allergen Bet v 1, a major allergen for >100 million allergic patients. Monoclonal and polyclonal Abs raised against Bet v 1-derived peptides were used to compete with allergic patients' IgE binding to Bet v 1 to search for sequences involved in IgE recognition. Strong inhibitions of patients' IgE binding to Bet v 1 (52-75%) were obtained with mAbs specific for two peptides comprising aa 29-58 (P2) and aa 73-103 (P6) of Bet v 1. As determined by surface plasmon resonance, mAb2 specific for P2 and mAb12 specific for P6 showed high affinity, but only polyclonal rabbit anti-P2 and anti-P6 Abs or a combination of mAbs inhibited allergen-induced basophil degranulation. Thus, P2 and P6 define a surface patch on the Bet v 1 allergen, which allows simultaneous binding of several different IgE Abs required for efficient basophil and mast cell activation. This finding explains the high allergenic activity of the Bet v 1 allergen. The approach of using peptide-specific Abs for the mapping of conformational IgE epitopes on allergens may be generally applicable. It may allow discriminating highly allergenic from less allergenic allergen molecules and facilitate the rational design of active and passive allergen-specific immunotherapy strategies.
authors: Division of Immunopathology, Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria.
authors: Anna
authors: A
authors: Gieras
authors: Petra
authors: P
authors: Cejka
authors: Katharina
authors: K
authors: Blatt
authors: Margarete
authors: M
authors: Focke-Tejkl
authors: Birgit
authors: B
authors: Linhart
authors: Sabine
authors: S
authors: Flicker
authors: Angelika
authors: A
authors: Stoecklinger
authors: Katharina
authors: K
authors: Marth
authors: Anja
authors: A
authors: Drescher
authors: Josef
authors: J
authors: Thalhamer
authors: Peter
authors: P
authors: Valent
authors: Otto
authors: O
authors: Majdic
authors: Rudolf
authors: R
authors: Valenta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity / Q000276:immunology*; D052179:Antigens, Plant / Q000737:chemistry / Q000276:immunology*; D001491:Basophils / Q000276:immunology; D029662:Betula / Q000276:immunology; D001667:Binding, Competitive; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping / Q000379:methods*; D018985:Epitopes, B-Lymphocyte / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology; D007073:Immunoglobulin E / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000276:immunology; D011058:Pollen / Q000276:immunology; D011817:Rabbits; D017386:Sequence Homology, Amino Acid
chemical_list: D000911:Antibodies, Monoclonal; D052179:Antigens, Plant; D018985:Epitopes, B-Lymphocyte; D010455:Peptides; C061312:Bet v 1 allergen, Betula; D007073:Immunoglobulin E