Which substance is elevated during a type 1 hypersensitivity reaction?

During a type 1 hypersensitivity reaction, IgE levels are elevated. This type of hypersensitivity is often associated with allergic responses, such as asthma, hay fever, and food allergies. When an individual is exposed to an allergen, their immune system mistakenly identifies it as a harmful substance, leading to the production of IgE antibodies.

These IgE antibodies bind to mast cells and basophils, which are types of white blood cells involved in immune responses. Upon subsequent exposure to the same allergen, the bound IgE triggers these cells to release histamine and other inflammatory mediators. This release is what causes the symptoms of allergic reactions, such as itching, swelling, and difficulty breathing. The specificity of IgE for such reactions is what makes it the key immunoglobulin involved in type 1 hypersensitivity.

Other immunoglobulins like IgG, IgM, and IgA play various roles in the immune system but are not specifically elevated during type 1 hypersensitivity reactions. IgG is generally associated with secondary immune responses and long-term immunity; IgM is the first antibody produced in response to an infection; and IgA is predominantly found at mucosal surfaces, protecting against pathogens entering the body through those routes.