IL4 and asthma: Interleukin-4 (IL-4), IL-13, and IL-5 are type 2 (Th2) cytokines that support the vital role of Th2 lymphocytes in asthma pathogenesis by reducing the release of immunoglobulin (Ig)E and eosinophil infiltration into lung tissues, which accelerate the process of allergic asthma [4, 5].