Human IL-1 receptor antagonist/ IL-1RA ELISA Kit

Kit Components

 1. Recombinant Human IL-1RA  standard: 2 vials

 2. One 96-well plate coated with Human IL-1RA  Ab

 3. Sample diluent buffer: 12 mL - 1

 4. Detection antibody: 130 µL, dilution 1:100

 5. Streptavidin-HRP: 130 µL, dilution 1:100

 6. Antibody diluent buffer: 12 mL x1   

 7. Streptavidin-HRP diluent buffer: 12 mL x1

 8. TMB developing agent: 10 mL x1

9. Stop solution: 10 mL x1

10. Washing solution (20x): 25 mL x1

Background

Interleukin-1 receptor antagonist (IL-1ra), also known as IL-1F3, ICIL-1RA, IL-1 inhibitor, is a member of the IL-1 family. Human IL-1ra is synthesized as a 177 aa precursor protein composed of a 25 aa signal sequence and a 152 aa mature region. Mature human IL-1ra is 77% and 82% aa identical to mouse and canine IL-1ra, respectively, and shows species cross-reactivity on mouse cells. It is reported that IL-1ra is expressed on diverse cells including monocytes, Sertoli cells, hepatocytes, adipocytes, synovial fibroblasts, mast cells, pancreatic β-cells, and intestinal epithelial cells.

IL-1 initiates a series of biological processes by binding to widely expressed IL-1 type I receptor (IL-1 RI). On endothelial cells (EC), IL-1 induces PGE2 and IL-6 release, generating fever, thrombocytosis, and hepatic acute phase protein production. In synovial joints, IL-1 induces chondrocyte NO production, leading to reduced collagen synthesis and chondrocyte apoptosis. IL-1 increases neutrophil counts, both in blood and tissue, and thus is able to promote a pro-inflammatory environment in multiple locations. IL-1ra blocks IL-1 action through competitive inhibition. Although IL-1ra fills the IL-1 binding site in IL-1 RI, it is unable to assist the formation of a signal-transducing IL-1 RI:IL-1 R Accessory protein (IL-1 R AcP) heterodimer complex. In other words, IL-1ra is a pure cytokine receptor antagonist that has no signal transduction-initiating activity.