Regulation of allergy by Fc receptors.
The aggregation of high-affinity IgE receptors (FcepsilonRI) on mast cells and basophils has long been known as the critical event that initiates allergic reactions. Monomeric IgE was recently found to induce a variety of effects when binding to FcepsilonRI. Upregulation of FcepsilonRI only requires binding, whereas other responses require FcepsilonRI aggregation. Interestingly, FcepsilonRI aggregation has recently been understood to generate a mixture of positive and negative intracellular signals. Mast cells and basophils also express low-affinity and, under specific conditions, high-affinity IgG receptors. When co-engaging these receptors with FcepsilonRI, IgG antibodies can amplify or dampen IgE-induced mast cell activation. On the basis of these findings, it has been proposed that FcRs can be used as targets and/or tools for new therapeutic approaches to allergies.
Bruhns
Pierre
P
Unité d'Allergologie Moléculaire et Cellulaire, Département d'Immunologie, Institut Pasteur, 25 rue du Docteur Roux, 75015 Paris, France.
Frémont
Sophie
S
Daëron
Marc
M
D000818:Animals; D001491:Basophils / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity / Q000188:drug therapy / Q000276:immunology*; D007073:Immunoglobulin E / Q000378:metabolism; D008407:Mast Cells / Q000276:immunology; D051379:Mice; D011961:Receptors, Fc / Q000037:antagonists & inhibitors / Q000502:physiology*; D017455:Receptors, IgE / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction
D011961:Receptors, Fc; D017455:Receptors, IgE; D007073:Immunoglobulin E