IL4, also known as Interleukin 4 isoform1, is a pleiotropic cytokine that has many biological roles, including the stimulation of activated B-cell and T-cell proliferation, and the differentiation of naive helper T-cell to Th2 cells. IL4 is a co-stimulator of DNA-synthesis and is induces the expression of class II MHC molecules on resting B-cells. It also enhances both secretion and cell surface expression of IgE and IgG1. Recombinant mouse IL4, was expressed in E.coli and purified by using conventional chromatography techniques