[The role of IgA in allergic disease].
Within the framework of immunological mechanisms involved in allergic forms, and view of the fact that immunoglobulins represent one of the cardinal points thereof, the attention is focused on the IgA, first getting a deeper insight into the current knowledge of their structure and localization, which has recently been added to with some important details. The models set forth are aimed to show the molecular organization of monomeric and polymeric IgA, and the functional significance of their different distribution in secretory and serous tissues, with particular stress on the action displayed by IgA specific bacterial proteases. Thus the problem of IgA synthesis and secretion, analyzing the model of formation of secretory IgA, and the defensive role they play in protecting the mucous surfaces, is tackled. Lastly, within the framework of IgA-specific immunodeficiencies, the pathogenetic mechanisms of the selective hypo-IgA, the variability of the IgA selective defect, and the pathology connected therewith, are examined with particular stress on the relationships between IgA and allergopathies along with the latest immunotherapy trends, understood as a supply of the lacking immunoglobulin class.