Interleukin 18 (IL-18), also known as interferon-gamma-inducing factor (IGIF) and IL-1gamma, is a cytokine which shares biologic activities with IL-12 and structural similarities with the IL-1 family of proteins. IL-18 was originally cloned from liver cells and has since been shown to be expressed by monocyte/macrophages, osteoblasts and keratinocytes. Caspase-1 (IL-1 beta-converting enzyme) has been implicated in the physiological processing of pro-IL-18 to IL-18. Similarly to IL-12, human IL-18 has been shown to enhance NK cell activity in PBMC cultures. Human IL-18 has also been found to induce the production IFN-gamma and GM-CSF while inhibiting the production of IL-10 by PBMC. On enriched human T cells, human IL-18 can enhance Th1 cytokine production and stimulate cell proliferation via an IL-2-dependent pathway. In the mouse system, IL-18 has been shown to be a costimulatory factor for the activation of Th1, but not Th2, cells. IL-18 was found to selectively enhance the FasL-mediated cytotoxicity of Th1, but not Th0 or Th2, cells. IL-18 has also been shown to induce activated B cells to produce IFN-gamma that inhibits IgE production.
Sample Type:Cell culture supernatants, serum, plasma, and tissue
Intended Use:The Human IL-18 BioAssay™ ELISA Kit is an enzyme-linked immunosorbent assay for the quantitative detection of Human IL-18 concentrations in cell culture supernatants, serum, plasma, and tissue.
Sensitivity:4pg/ml
Range:1000-15.625pg/ml
Specificity:Recognizes human IL-18.
Sample Volume:100ul/well
Test Principle:This assay employs the Sandwich immunoassay technique. An anti-h IL-18 monoclonal coating antibody is adsorbed onto microwells. IL-18 present in the sample or standard binds to antibodies adsorbed to the microwells. Following incubation unbound sample or standard are removed during a wash step. a Biotinylated anti-h IL-18 antibody is added and binds to IL-18 captured by the first antibody. Following incubation unbound Biotinylated anti-h IL-18 antibody is removed during a wash step. A Streptavidin-HRP is added and binds to Biotinylated anti-h IL-18 antibody. Following incubation unbound Streptavidin-HRP is removed during a wash step. A colored product is formed in proportion to the amount of IL-18 present in the sample. The reaction is terminated by addition of acid and absorbance is measured at 450nm. A standard curve is prepared from seven IL-18 standard dilutions and IL-18 sample concentration determined.
Storage and Stability:Store powder at 4°C liquid at -20°C. Store other components at 4°C. Stable for at least 6 months For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
