Purification, cloning, expression and biological characterization of an interleukin-1 receptor antagonist protein

Abstract

A human myelomonocytic cell line, U937, produced an interleukin-1 (IL-1) receptor antagonist protein (IRAP) which was purified and partially sequenced. A complementary DNA coding for IRAP was cloned and sequenced. The mature translation product of the cDNA has been expressed in Escherichia coli and was an active competitive inhibitor of the binding of IL-1 to the T-cell/fibroblast form of the IL-1 receptor. Recombinant IRAP specifically inhibited IL-1 bioactivity on T cells and endothelial cells in vitro and was a potent inhibitor of IL-1 induced corticosterone production in vivo.

Cytokine Gene Polymorphism in Idiopathic Nephrotic Syndrome Children

“…TNF-a is pro-inflammatory cytokine, and IL-4 and IL-6 are anti-inflammatory cytokines. Pro-inflammatory cytokines are of central importance in T and B-cell help and initiation of the immune response [18]. Minimal change nephrotic syndrome (MCNS) in children is frequently associated with allergy and immunoglobulin E production.…”

Correlation of polymorphic variation in the promoter region of the interleukin‐1β gene with secretion of interleukin‐1β protein

“…Extracellular mature IL-1␤ can promote production of matrix metalloproteinases and synthesis of prostaglandin, as well as other proinflammatory events. Because IL-1 activity is modulated by its natural antagonist, IL-1Ra (12), altered expression of IL-1␤ protein may affect this regulation at the cellular level, resulting in local expression of IL-1␤ protein where it mediates inflammatory responses and/or promotes the production of matrix metalloproteinases.…”

IL1RN (interleukin 1 receptor antagonist)

“…Note IL1RN (interleukin 1 receptor antagonist) was identified in 1990 by Carter and cols (Carter et al, 1990). It codes a protein that binds to interleukin 1 receptor (IL1R1) and inhibits the binding of interleukin 1 alpha and beta (IL1A and IL1B), blocking the biological activity of these two cytokines, this is the first interleukin 1 family member described that has antagonist function (Arend, 1991;Arend and Gabay, 2000).…”

“…IL1RN mRNA does not contain the AUUUA sequence that has been implicated in shortening the half-life of several cytokine mRNAs (Carter et al, 1990).…”