IL-1 beta (Interleukin-1 beta) is produced in response to inflammatory agents, infections, or microbial endotoxins. It plays a central role in immune and inflammatory responses, bone remodeling, fever, carbohydrate metabolism, and GH/IGF-I physiology. IL-1 beta dysregulation is implicated in many pathological conditions including sepsis, rheumatoid arthritis, inflammatory bowel disease, acute and chronic myelogenous leukemia, insulin-dependent diabetes mellitus, atherosclerosis, neuronal injury, and aging-related diseases. Intracellular cleavage of the IL-1 beta precursor by Caspase-1/ICE is a key step in the inflammatory response. IL-1 beta binds to IL-1 RI and IL-1 RII. The IL-1 receptor accessory protein (IL-1 RAcP) associates with IL-1 RI and is required for IL-1 RI signal transduction, and IL-1ra is a secreted molecule that functions as a competitive inhibitor of IL-1 bioactivity.