Recombinant Human IL-1β

IL-1R1 is an 80 kD transmembrane glycoprotein and a member of the Ig superfamily. IL-1 binds both IL-1R1 and IL-1R2. The ligands IL-1α and IL-1β only commence when binding IL-1R1 because IL-1R2 acts as a decoy receptor and competitively antagonizes the binding of IL-1α and IL-1β, thereby reducing their biological effects. Binding of the ligands to IL-1R1 is enhanced by an accessory protein, IL-1R-AcP. IL-1α can exist as either a 31 kD precursor or an 18 kD mature form. IL-1α is a proinflammatory cell-associated cytokine and IL-1β is a 17.5 kD proinflammatory secreted cytokine. Both IL-1α and IL-1β bind to the same receptor and have similar properties that include stimulation of thymocyte proliferation via IL-2 release, B-cell maturation and proliferation, mitogenic FGF-like activity and the ability to stimulate the release of prostaglandin and collagenase from synovial cells. Furthermore, IL-1β mediates a variety of immune and inflammatory responses. IL-1β is a major cause of severe inflammation in the mouse model of Crohn’s Disease, which makes IL-1β an important target for this disease.