Anti-human IL-4 mAb (IL4-3), PF488P

Interleukin 4 (IL-4) is produced primarily by Th2 cells, mast cells, eosinophils, and basophils. IL-4 was first identified to costimulate B cell growth; the cytokine is essential for B cell secretion of IgE and augments the production of IgG1 in vivo. In addition to regulating B cell growth and immunoglobulin secretion, IL-4 also affects T cells. In vitro, IL-4 promotes T cell growth and can induce cytolytic T cell activity. IL-4 also induces the differentiation of naive CD4 T cells into Th2 cells, which are characterized by their capacity to secrete the cytokines IL-4, IL-5, and IL-10 upon activation, while simultaneously inhibiting the generation of Th1 cells.