Human IL-18 ELISA Kit

Interleukin 18 (IL-18) is an 18 kDa cytokine which is identified as a costimulatory factor for production of interferon-? (IFN-?) in response to toxic shock. It shares functional similarities with IL-12. IL-18 is synthesized as a precursor 24 kDa molecule without a signal peptide and must be cleaved to produce an active molecule. IL-1? converting enzyme (ICE, caspase-1) cleaves pro-IL-18 at aspartic acid in the P1 position, producing the mature, bioactive peptide that is readily released from the cells. It has been reported that IL-18 is produced from dendritic cells, activated macrophages, Kupffer cells, keratinocytes, intestinal epithelial cells, osteoblasts, adrenal cortex cells and murine diencephalons. IFN-? is produced by activated T and NK cells and plays critical roles in the defense against microbial pathogens. IFN-? activates macrophages, enhances NK activity and B cell maturation, proliferation and Ig secretion, induces MHC class I and II antigens expression, and inhibits osteoclast activation. IL-18 acts on T helper 1-type (Th1) cells, and in combination with IL-12 strongly induces production of IFN-? by these cells. Pleiotropic effects of IL-18 have also been reported, including enhancement production of IFN-? and GM-CSF in peripheral blood mononuclear cells, production of Th1 cytokines, IL-2, GM-CSF and IFN-? in T cells, enhancement of Fas ligand expression by Th1 cells. The “Human IL-18 ELISA Kit” is a useful reagent for specifically measuring human IL-18 with high sensitivity by ELISA. This Kit does not detect 1 ng/mL of various cytokines, such as human IFN-?, IFN-?, IL-1?, IL-4, IL-5, IL-6, IL-10, IL-12, GM-CSF and murine IL-18. The results were all bellow the detection limit of 12.5 pg/mL.