BACKGROUND Th2 cells have long been considered responsible for the switching of B cells to production of IgE during cognate interaction, primarily due to their expression of CD40L and secretion of IL-4. This concept has been challenged by the more recent definition of follicular helper T cells (Tfh) as the key T cell subset in B cell isotype switching, due to their physical location at the boun...

Production of specific immunoglobulin (Ig)E is the characteristic abnormality of atopy. IgE is produced by B lymphocytes under the influence of interleukin (IL)4 and IL-13. IgE binds to high-affinity IgE receptors (Fc«RI) on mast cells to induce degranulation and mediator synthesis. IL-4 enhances the activation of Fc«RI to augment the production of cytokines and lipid mediators. These receptors...

The b-chain of the high-affinity receptor for IgE (FceRI) plays a crucial role for amplification of the intracellular signaling in mast cells upon FceRI cross-linking by IgE antigen complexes (IgE Ag). Some monomeric IgE as well as IgE Ag stimulate FceRI-signaling pathways, leading to cell activation, whereas the biological functions of the b-chain in the monomeric IgE-mediated mast cell signal...

The role of IgE in allergic disease mechanisms is performed principally through its interactions with two receptors, FcεRI on mast cells and basophils, and CD23 (FcεRII) on B cells. The former mediates allergic hypersensitivity, the latter regulates IgE levels, and both receptors, also expressed on antigen-presenting cells, contribute to allergen uptake and presentation to the immune system. We...

Production of specific immunoglobulin (Ig)E is the characteristic abnormality of atopy. IgE is produced by B lymphocytes under the influence of interleukin (IL)4 and IL-13. IgE binds to high-affinity IgE receptors (Fc«RI) on mast cells to induce degranulation and mediator synthesis. IL-4 enhances the activation of Fc«RI to augment the production of cytokines and lipid mediators. These receptors...

Background Local allergic rhinitis (LAR) is characterized by negative skin testing and serum specific IgE. Diagnosis is based on nasal provocation test (NPT), very sensitive but time-consuming, and/or presence of local synthesis of specific IgE (sIgE) which shows low sensitivity (22%). The aim of the study was to evaluate the presence of specific D. pteronyssinus (DP) activation of basophils by...

Background Atopic dermatitis is a common chronic skin disorder which is a subset of atopy. Atopy refers to a genetic predisposition to respond immunonologically to allergens which are generally harmless, causingover production of immunoglobulin E (IgE) antibodies. IgE synthesis is dependent on the activation of CD4+ Th2 subset and their secretion of cytokines including IL 4 and IL 13. This stud...

Background: The etiology of urticaria is recognized only in a minority of cases. Allergies to a wide variety of agents have been suspected, as well as hyper reactivity to food additives or drugs. Recently, autoimmune reaction to immunoglobulin E (IgE) and later to high-affinity IgE receptors on mast cells has been reported. The aim of this study was to show elevated serum IgE levels in the pati...