Which antibody class is found bound to the surface of mast cells and basophils?

The antibody class that is found bound to the surface of mast cells and basophils is IgE. This particular immunoglobulin plays a critical role in the immune system, especially in allergic responses and in providing protection against parasitic infections. When IgE binds to allergens, it triggers the mast cells and basophils to release histamine and other mediators, which leads to the clinical manifestations associated with allergic reactions, such as inflammation, swelling, and other allergy symptoms.

IgE's specificity allows these immune cells to respond to specific antigens, making it an essential component of the allergic response and the body’s defense against certain external threats. Understanding the role of IgE is fundamental in fields such as immunology and allergy management, emphasizing its importance in both protective and pathological processes.