The Immunoglobulin E (IgE) receptor, also known as FcεRI (Fc epsilon receptor I), is a transmembrane protein found on the surface of immune cells called mast cells and basophils. It plays a crucial role in mediating allergic reactions and immune responses.
The IgE receptor consists of four subunits: one alpha chain, one beta chain, and two disulfide-linked gamma chains. The alpha chain binds to IgE antibodies, specifically the Fc portion of IgE. IgE antibodies are produced by the immune system in response to certain allergens or parasites.
When an individual is exposed to an allergen, such as pollen or pet dander, the allergen binds to the IgE antibodies on the IgE receptor. This interaction triggers the activation of mast cells and basophils, leading to the release of various chemical mediators, including histamine. Histamine causes allergic symptoms such as itching, sneezing, and inflammation.
In addition to its role in allergies, the IgE receptor also plays a role in defending against certain parasites, such as worms. It allows for the recruitment of other immune cells to the site of parasite invasion, leading to their elimination.
Overall, the IgE receptor is a critical component of the immune system's response to allergens and parasites. Its activation triggers the release of inflammatory mediators, ultimately leading to the characteristic symptoms of allergies and the elimination of parasites from the body.
