Human Interleukin‐1 receptor antagonist High yield expression in E. coli and examination of cysteine residues

Abstract
The human IL‐1 receptor antagonist (IL‐1ra) was produced in a high yield E. coli expression system, and was purified in a rapid two‐step purification, This recombinant IL‐1ra molecule possessed full binding activity to the IL‐1 receptor (type I) and totally inhibited IL‐1‐induced PGE2 production by human dermal fibroblasts. Radioalkylation and analysis of V8‐derived IL‐1ra peptides indicate that the four cysteines present in the IL‐1ra are not disulphide‐linked.