One of the most potent pro-inflammatory mediators is the early-acting cytokine interleukin-1 (IL-1), whose actions are regulated by the structurally related IL-1 receptor antagonist (IL-1 RA). IL-1 RA is a competitive IL-1 inhibitor and a powerful anti-inflammatory agent. Also, Several autoimmune and inflammatory diseases have been associated with an allelic polymorphism of the IL-1 RA gene. Recombinant human IL-1 RA was expressed in E. coli and purified by using conventional chromatography techniques. Synonyms: IL1RN, IL1F3, IL1RA, Interleukin-1 receptor antagonist , IL-1ra, IL-1RN, IRAP, IL1 inhibitor, ICIL-1RA, Anakinra, Interleukin-1 receptor antagonist protein, ICIL 1RA, IL1 inhibitor, ICIL1RA,. NCBI no.: NP_776214