The role of antigen-presenting cells in the regulation of allergen-specific T cell responses

Allergic reactions in atopic patients follow from a generalized enhanced po larization of Th cells, predominantly imposed by factors derived from antig en-presenting cells from a pathogen-stressed tissue; these sample informati on not only on antigen structures but also on the nature of the stress. Ant igen-presenting cells of atopic individuals show aberrant characteristics w hich, through a highly interactive communication network, play an active ro le in aberrant Th-cell polarization. This generalized bias may follow from intrinsic abnormalities of antigen-presenting cells and also from a low deg ree of cross-regulation by micro-organisms.