Description: Mouse IL-1 alpha, also called Lymphocyte Activating Factor (LAF), Endogenous Pyrogen (EP), Leukocyte Endogenous Mediator (LEM), and Mononuclear Cell Factor (MCF), is an ~17 kDa factor produced by a wide variety of cells, including macrophages, dendritic cells, T and B cells. IL-1 alpha is mostly cell-associated, with 23% amino acid homology with IL-1 beta. The immune regulatory role of IL-1 alpha is exerted on a wide range of cells including lymphocytes, epithelial cells and fibroblasts. In vivo, it induces hypotension, fever, and acute phase response.