IL13 (Interleukin 13) is a cytokine with a weight of 12-kDa, expressed by CD4 T helper 2 (Th2) cells, basophils, eosinophils, mast cells, invariant natural killer T cells, and type 2 innate lymphoid cells. IL-13 is primarily produced by TH2 cells, but it is also secreted by other T helper cell subsets CD8+ T cells, mast cells, eosinophils and basophils following activation. IL-13 induces proliferation and immunoglobulin E (IgE) synthesis by human B cells, suggesting that it may play a role in the pathogenesis of IgE-mediated allergic diseases. Moreover, IL-13 inhibits production of proinflammatory cytokines and chemokines by monocytes/macrophages both in vitro and in vivo, indicating that IL-13 also has important anti-inflammatory properties. IL4 (Interleukin 4), also referred to IL-4, BSF-1 (B-cell Stimulatory Factor 1) or BCGF-1, is a 17.5 kDa glycoprotein of 153 amino acids that is encoded on the chromosome 5q31.1. It is a multifunctional cytokine produced in response to receptor activation by B cells, basophils, Th2-type CD4+ T cells, and mast cells. IL-4 rescues B cells from apoptosis, increasing their survival ability, and responsible for immunoglobulin (Ig) isotype switching to IgG1 and IgE. It is essential for the differentiation and growth of the Th2 and as a STAT-6 signaling-dependent protein shifting the Th balance toward a Th2-mediated response. IL-4 as a growth factor plays a primary regulatory role in allergic responses and facilitates humoral responses to combat extracellular pathogens.