Mapping of human T-cell epitopes of allergens.

Allergens are characterized by their ability to be bound by gE. The Swiss-Prot protein database currently lists a partial or complete amino acid sequence of in excess of about 350 allergens. It is not clear how allergens participate in the process of allergic sensitization, the generation of specific T-helper type 2 (Th2) lymphocytes, which play a crucial role in stimulating B lymphocytes to produce allergen-specific IgE.T-helper (Th) cells play a key role in the regulation of immune responses. The recognition of antigen by T cells is complex and it can trigger qualitatively differential signaling. Therefore, it is conceivable that epitopes or antigenic determinants recognized by Th cells may influence the quality of immune response. The aim of this chapter is to describe the way in which T-cell epitopes can be identified (mapped). This is particularly important because knowledge of the precise T-cell epitopes of allergens can give important information on the pathogenesis of allergy and can help to develop better preparations for the diagnostics and/or immunotherapy of allergy.