Description
IL-4 (Interleukin 4, B cell stimulatory factor) is a pleiotropic cytokine produced by activated T cells, mast cells and basophils. IL-4 has many different functions including promoting proliferation and differentiation of immunologically competent cells. One of its main functions is regulating differentiation of naive CD4+ T cells into helper Th2 cells, the other main function is regulating B cells IgE and IgG1 production. Human IL-4 shows 50% homology with mouse IL-4, but its activities are species-specific and human IL-4 shows no activity on murine and rat cells