Explain how a type I, or immediate, hypersensitivity is different from a typical primary immune response

Question

What will be an ideal response?

Answer 1

Type I, or immediate, hypersensitivity reactions occur when an individual reacts to a foreign antigen, an allergen. In the first exposure of an individual to an allergen, (1 ) an allergen binds a B cell, and (2 ) the B cell differentiates into plasma cells that begin to secrete antibodies, just as they normally would when exposed to a foreign antigen. But there is one key difference between this response and a normal response: The plasma cells secrete IgE instead of IgG or IgM. This first exposure generates a primary immune response, which occurs slowly and produces few symptoms, but does result in the formation of large numbers of IgE molecules that coat mast cells and basophils. Subsequent exposures to the allergen in a sensitized person result in rapid responses that occur within a few minutes.