Structural and functional analyses of IgE epitopes and their biological relevance ; Strukturelle und funktionelle Analysen von IgE Epitopen und ihrer biologischen Relevanz

So far, the detailed knowledge of complex interactions of antibodies with their corresponding epitopes and the essential requirements for triggering complex mechanisms, especially in pathophysiological backgrounds like allergies, is only restricted. One reason for this deficit is the lack of monoclonal human antibodies, especially of the allergy relevant isotype IgE, occurring only with very low concentrations in the human serum and therefore turning the identification, characterization and interaction analysis of epitopes into a major challenge. Furthermore the availability of allergenic target structures and a precise knowledge about their properties on a molecular level are essential to understand allergic reactions in more detail. At present, available recombinant technologies open up a wide range of possibilities to obtain detailed molecular insights into complex binding patterns of antibodies to their antigens. The aim of this work was the evaluation of B cell IgE epitopes and their biological relevance by investigations of antibody interactions with their antigens, using recombinant methodologies on different molecular levels in the context of allergy. One of the major reasons for IgE-mediated anaphylaxis are hypersensitivities due to hymenoptera venoms, which represent an ideal clinical condition for studying type I allergic reactions. The hymenoptera venom allergens Api m 1 and Api m 10 were recombinantly produced in different cell lines resulting in proteins with a varying degree of cross-reactive carbohydrate determinants (CCDs). They were used as tools for precise analyses of specific patients IgE reactivities against CCDs or peptidic epitopes and for a detailed reactivity dissection recombinant approaches could be established. Additionally the evaluation of the significance of the new venom component Api m 10 and the assessment of its allergenicity was possible. The low molecular weight honeybee venom allergen and putative protease inhibitor Api m 6 was immunochemically characterized and its ...