Role of IgE in the Pathogenesis of Non-Atopic Asthma. (360G-Wellcome-091449_Z_10_Z)

We propose the first comprehensive analysis of all potential mechanisms of mast cell activation by IgE in the blood and bronchial mucosa of 12 non-atopic and 12 atopic asthmatics and 12 controls. We plan to analyse IgE specificities in serum and protein extracts from the bronchial mucosa of routinely tested (common) allergens and rare allergens, including super-allergens from S. aureus, using an allergen microarrays and ELISA, and unknown, (possibly auto-allergens) using a random peptide phage display library. We will assay serum and extracts for pseudo-allergens anti-IgE and the anti-high affinity IgE receptor. We will clone patient B cells to examine the monoclonal IgEs for cytokinergic activity, VH-region families (to look for evidence B cell super-allergen activity) and the activity of free light-chains. Our study will make use of novel techniques that we or our collaborators have developed, such as B cell cloning, screening for all known allergens using allergen microar rays and for unknown allergens using phage display of a peptide library, and assays of cytokinergic IgE. This research will provide the first definitive test of the pathogenic activity of IgE in non-atopic asthma with the added value of defining a diversity of mechanisms to inform future diagnosis and therapy.