Immunological and non immunological mechanisms in urticaria
Bérard, F.; Saint-Mezard, P.; Cousin, F.; Mecheri, S.; Nicolas, J-F.
Annales de Dermatologie et de Venereologie 130 Spec No 1: 1s10-1s15
2003
ISSN/ISBN: 0151-9638 PMID: 12843804 Document Number: 560782
Urticaria involve mast cell activation which could be mediated by immunological or non-immunological mechanisms. Interaction of allergens with the IgE/IgE receptor at the surface of mast cells has been postulated as the main immunologic type of mast cell activation. However, recent experimental and clinical studies have highlighted the existence of other mechanisms involving specific antibodies and T cells. IgG antibodies of different specificities (anti-IgE and/or anti-IgE receptor autoantibodies) have been characterized in a subgroup of patients sufferenig from chronic "autoimmune" urticaria. Circulating immune complexes may activate mast cells by interaction with the membrane-bound receptor for IgG. Interaction of mast cells with specific T cells could induce mast cell activation. Thus, immune-mediated urticaria appears to be secondary to different types of mast cell activation which could explain the various clinical presentation of the disease.