Recombinant Human IL-1 beta (His, Strep)

Interleukin 1β (IL1β or IL1B), also known as catabolin, is a member of the interleukin 1 family of cytokines. IL1 refers to two pleiotropic cytokines, IL-1α (IL-1F1) and IL-1β (IL-1F2), which are products of different genes. IL-1α and IL-1β are structurally related peptides that share about 21% amino acid (aa) identity in humans. Both proteins are produced by a wide variety of cells in response to inflammatory factors, infections, or microbial endotoxins. While IL-1α and IL-1β are independently regulated, they bind to the same receptor and exert the same biological role. IL-1RI binds directly to IL-1α or IL-1β and then to the IL-1R accessory protein (IL-1R3/IL-1RAcP) to form a high-affinity receptor complex capable of signal transduction. IL-1RII has a high affinity for IL-1β but acts as a decoy receptor and a negative regulator of IL-1β activity. Human IL-1β cDNA encodes a precursor of 269 amino acids. The cysteine protease IL-1β convertase (Caspase-1/ICE) cleaves the 116aa propeptide intracellularly to produce active cytokines [5-7]. The 17 kDa mature human IL-1β has 96% aa sequence homology with rhesus macaques and 67%-78% aa sequence homology with dogs, cotton mice, horses, cats, mice, pigs, and rats.