What type of immunoglobulin is primarily involved in Type I allergic responses?

Type I allergic responses are primarily mediated by immunoglobulin E (IgE). This type of immunoglobulin plays a critical role in the immune system's response to allergens such as pollen, pet dander, and certain foods.

Upon exposure to an allergen, IgE antibodies are produced by plasma cells, a type of white blood cell. These IgE antibodies then bind to specific receptors on mast cells and basophils, which are types of cells involved in the immune response. When the same allergen is encountered again, it cross-links the IgE on the surface of these cells, leading to their activation and the release of various inflammatory mediators, including histamine. This process results in the symptoms associated with allergy, such as itching, swelling, and bronchoconstriction.

In contrast, other immunoglobulin types such as IgA, IgG, and IgM have distinct roles in the immune response. For instance, IgA is primarily found in mucosal areas and plays a key role in mucosal immunity, while IgG is the most abundant antibody in circulation and is involved in opsonization and neutralizing pathogens. IgM, on the other hand, is the first antibody produced in response to an infection. Thus