RECOMBINANT ALLERGEN-SPECIFIC ANTIBODY FRAGMENTS - TOOLS FOR DIAGNOSIS, PREVENTION AND THERAPY OF TYPE-I ALLERGY

Type I allergy represents a hypersensitivity occurring in almost 20% o f the population that is based on the recognition of innocuous airborn antigens (pollen, mite, mould and pet allergens) by specific immunogl obulin E. Allergic symptoms (e.g. allergic rhinitis, conjunctivitis, a sthma) are caused by the release of biological mediators from effector -cells after allergen-induced crosslink of receptor-bound IgE, Here we discuss strategies to obtain recombinant allergen-specific antibody f ragments (Fabs) from mouse and human cell lines as well as directly fr om allergic patients lymphocytes via the combinatorial library technol ogy. It is suggested to use recombinant allergen-specific Fabs for the standardization of allergen extracts currently used for diagnosis and treatment, to determine allergen contents in allergen sources and the environment to allow preventive measures and to use allergen-specific Fabs as therapeutic tools to interfere with the allergen-IgE interact ion. The latter appears possible because IgE represents the least abun dant class of immunoglobulins and there is increasing evidence for a l imited diversity among allergens and their B-cell epitopes, Moreover, allergic effector reactions are mostly confined to accessible target o rgans so that a local application of competing Fabs prior to allergen exposure might represent a feasible therapeutic approach.