<prompt> Eosinophil are activated byIL 1IL5IL4IL6  <response>: ref Robbins 8e p200; IL 5 is required for the development and maturation of eosinophil Through binding to the interleukin-5 receptor, interleukin 5 stimulates B cell growth and increases immunoglobulin secretion - primarily IgA. It is also a key mediator in eosinophil activation. 