IgE, short for immunoglobulin E, is a type of antibody in the immune system that is released to help combat foreign substances and allergens that have entered the body. Abnormal IgE levels can be a sign of parasite infection, an allergic reaction or some other environmental sensitivity. IgE levels are determined through simple blood tests and can assist in the diagnosis of autoimmune diseases, allergies and cancers.
IgE is one of five types of antibodies, also known as immunoglobulins, in the body. Immunoglogulins are produced by the immune system in response to bacteria, viruses, fungus and other allergens that have entered the body. IgE and the other antibodies attack the foreign substance in an attempt to prevent sickness and cellular damage.
IgE antibodies are located in the lungs, skin and mucous membranes of the body. These antibodies cause reactions when a sensitive individual comes in contact with environmental allergens such as pollen, fungus spores and pet dander. Individuals who are allergic or intolerant to dairy or certain medications also will release IgE after ingestion.
Individuals with hypersensitivity or several allergies and intolerances generally have a higher IgE antibody level.
IgE is one of five types of antibodies in the body. The others include IgA antibodies, which are found in the nose, throat, ears, tears, eyes, digestive tract, saliva, blood and vagina and are a defense against outside foreign substances. IgG antibodies are the most common antibodies. They are found in all bodily fluids and are the body's defense against viral infection and bacteria. IgM antibodies are the large and are located in the blood and lymph fluid. IgM antibodies respond to infection. Lastly, IgD antibodies are in the chest and stomach tissues, but their exact purpose is unclear to medical professionals.
Concentration of IgE is very low in the body. A normal IgE level is 4.2-595 U/mL or 0.05 percent of the IgG concentration. High IgE levels can be a sign of infection, allergic reaction, autoimmune disease or the presence of cancer. Low levels of IgE are hard to detect and usually are associated only with rare immunodeficiency diseases.