Epitopes described in "Spatial clustering of the IgE epitopes on the major timothy grass pollen allergen Phl p 1: importance for allergenic activity."

Article Authors:Sabine Flicker; Peter Steinberger; Tanja Ball; Maria-Theresa Krauth; Petra Verdino; Peter Valent; Steve Almo; Rudolf Valenta
Article Title:Spatial clustering of the IgE epitopes on the major timothy grass pollen allergen Phl p 1: importance for allergenic activity.
Reference Detail
Reference ID:1005347
Abstract:BACKGROUND: The major timothy grass pollen allergen Phl p 1 is one of the most potent and frequently recognized environmental allergens. OBJECTIVE: We sought to study at a molecular and structural level the IgE recognition of Phl p 1 and its relation to allergenic activity. METHODS: Monoclonal human IgE antibody fragments specific for Phl p 1 and group 1 allergens from various grasses were isolated from a combinatorial library made of lymphocytes from patients with grass pollen allergy. Recombinant Phl p 1 fragments and the 3-dimensional structure of Phl p 1 were used to localize the major binding site for the IgE antibodies. A rPhl p 1 fragment containing this binding site was expressed in Escherichia coli, purified, and tested for IgE reactivity and allergenic activity with sera and basophils from patients with grass pollen allergy. RESULTS: Monoclonal antibodies, as well as polyclonal serum IgE, from patients with grass pollen allergy defined a C-terminal fragment of Phl p 1 that represents a sterically oriented portion on the Phl p 1 structure. This Phl p 1 portion bound most of the allergen-specific IgE antibodies and contained the majority of the allergenic activity of Phl p 1. CONCLUSION: IgE recognition of spatially clustered epitopes on allergens might be a general factor determining their allergenic activity. CLINICAL IMPLICATIONS: Geographic distribution of IgE epitopes on an allergen might influence its allergenic activity and hence explain discrepancies between diagnostic test results based on IgE serology and provocation testing. It might also form a basis for the development of low allergenic vaccines.
Affiliations:Department of Pathophysiology, Center for Physiology and Pathophysiology, Medical University of Vienna, Austria.
Reference Type:Literature
PubMed ID:16750995
Journal:J Allergy Clin Immunol
Journal Volume:117
Article Pages:1336-43
Journal ISSN:0091-6749
Article Chemical List:Allergens;Immunodominant Epitopes;Peptide Fragments;Plant Proteins;PHLPI protein, Phleum pratense;Immunoglobulin E
Article MeSH List:Allergens(genetics; immunology; metabolism ); Binding Sites(immunology ); Cross Reactions; Epitope Mapping; Humans; Immunodominant Epitopes(immunology; metabolism ); Immunoglobulin E(metabolism ); Peptide Fragments(genetics; immunology; metabolism ); Phleum(immunology ); Pilot Projects; Plant Proteins(genetics; immunology ); Pollen(immunology ); Rhinitis, Allergic, Seasonal(immunology; metabolism )
Curation Last Updated:2014-10-03 20:39:56