Description: The 11B11 antibody reacts with mouse interleukin-4 (IL-4), a 14 kD cytokine. The 11B11 antibody is a neutralizing antibody. Mouse IL-4, also known as BCDF, BCGF-1 and BSF-1, is secreted by activated Th2 and natural killer T cells, and to a lesser extent by Th1 and mast cells. IL-4 is species-specific and promotes proliferation and differentiation of B cells. IL-4, in conjunction with other signals such as CD40, induces Ig isotype switching of B cells and the upregulation of surface MHC class II and CD23.