Mechanisms of Allergic Inflammation and IgE Analysis in Clinical Practice
Regina Emužytė, Ingrida Pumputienė, Regina Firantienė
Allergic inflammation is most important in the development of allergic diseases. All allergic reactions according to their immunologic mechanism are classified into four basic types. Type I allergic reactions (atopic diseases) are a major health problem. IgE sensitization against allergens increased up to 50% together with an increase in allergic disease up to 30% in the popul ation. S. G. O. Johansson in Sweden, K. Ishizaka and T. Ishizaka in the United States in 1966 simultaneously discovered immunoglobulin E and its role in the triggering of allergic reactions. The pathophysiology of allergic disease is multifactorial involving an intricate network of interactions among cells, mediators and especially cytokines. In atopic subj ects all ergen induces activation and/or proliferation of cells having the Th2 cytokine profile. Expression of Th2 cytokines is critical in the induction of IgE synthesis. IL-4 plays the most crucial role as a switching factor of B cells from IgM/IgG to the IgE antibody isotype. Acute phase of type I reaction is directly associated with mast cell aclivaf tion, preformed active mediators as histamine and lipid mediators. Late (inflammatory) phase of type I reaction is mainly induced by cytokines and directly associated with eosinophil activation. Late phase is clearly important in the development of chronic allergic disease. Changes in the balance between allergen-specific T-Reg cells and Th2 and/or Th1 cells are crucial in the development of allergic diseases. Investigations of immunological mechanisms in allergic inflammation are important for more effective diagnostics, prevention and therapy of allergy.
Keywords: allergy, classification, allergic inflammation, mediators, cytokines, IgE, mast cell, eosinophil, Th2 cell.