Interleukin 23 （IL-23） is a heterodimeric cytokine composed of two disulfide-linked subunits，a p19 subunit that is unique to IL-23，and a p40 subunit that is shared with IL-12. The p19 subunit has homology to the p35 subunit of IL-12，as well as to other single chain cytokines such as IL-6 and IL-11. The p40 subunit is homologous to the extracellular domains of the hematopoietic cytokine receptors. Mouse p19 cDNA encodes a 196aa residue precursor protein with a putative 19aa signal peptide and 177aa mature protein. Human and mouse p19 share 70%aa sequence identity. Although p19 is expressed by activated macrophages，dendritic cells，T cells，and endothelial cells，only activated macrophages and dendritic cells express p40 concurrently to produce IL-23. The functional IL-23 receptor complex consists of two receptor subunits，the IL-12 receptor beta 1 subunit （IL-12 R beta 1） and the IL-23-specific receptor subunit （IL-23 R）. IL-23 has biological activities that are similar to，but distinct from IL-12. Both IL-12 and IL-23 induce proliferation and IFN-gamma production by human T cells. While IL-12 acts on both naive and memory human T cells，the effects of IL-23 is restricted to memory T cells. In mouse，IL-23 but not IL-12，has also been shown to induce memory T cells to secret IL-17，a potent proinflammatory cytokine. IL-12 and IL-23 can induce IL-12 production from mouse splenic DC of both the CD8- and CD8+ subtypes，however only IL-23 can act directly on CD8+ DC to mediate immunogenic presentation of poorly immunogenic tumor/self peptide.Sample Type：Cell culture supernatants，serum，plasma，and tissueIntended Use：The Human IL-23 BioAssay ELISA Kit is an enzyme-linked immunosorbent assay for the quantitative detection of Human IL-23 concentrations in cell culture supernatants，serum，plasma，and tissue.Sensitivity：15pg/mlRange：31.25-2000pg/mlSpecificity：Recognizes human IL-23.Sample Volume：100ul/wellTest Principle：This assay employs the Sandwich immunoassay technique. An anti-h IL-23 monoclonal coating antibody is adsorbed onto microwells. IL-23 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-23 antibody is added and binds to IL-23 captured by the first antibody. Following incubation unbound Biotinylated anti-h IL-23 antibody is removed during a wash step. A Streptavidin-HRP is added and binds to Biotinylated anti-h IL-23 antibody. Following incubation unbound Streptavidin-HRP is removed during a wash step. A colored product is formed in proportion to the amount of IL-23 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-23 standard dilutions and IL-23 sample concentration determined.Kit Components：Aluminium pouches with a Microwell Plate： 8x12Standard： 2xVialBiotinylated antibody： 2xVialStreptavidin-HRP： 2xVialAssay Buffer （25ml/Vial）： 2xVialWash Buffer Concentrate 20x （30ml/Vial）： 1xVialTMB Substrate Solution： 1x12mlStop Solution （12ml/Vial）： 1xVialPlate Covers- Adhesive strips： 3xstripsInstruction： 1xStorage 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.
