Interleukin-1 (IL-1) is a name that designates two proteins,IL-1 alpha and IL-1 beta,which are the products of distinct genes,but which show approximately 25%aa sequence identity and which recognize the same cell surface receptors. Although IL-1 production is generally considered to be a consequence of inflammation,recent evidence suggests that IL-1 is also temporarily upregulated during bone formation and the menstrual cycle and can be induced in response to nervous system stimulation. In response to classic stimuli produced by inflammatory agents,infections or microbial endotoxins,a dramatic increase in the production of IL-1 by macrophages and various other cells is seen. IL-1 alpha and IL-1 beta are both synthesized as 31kD precursors that are subsequently cleaved into proteins with molecular weights of approximately 17,000. Neither precursor contains a typical hydrophobic signal peptide sequence and most of the precursor form of IL-1 alpha remains in the cytosol of cells,although there is evidence for a membrane-bound form of the precursor form of IL-1 alpha. The IL-1 alpha precursor reportedly shows full biological activity in the EL 4 assay. Among various species,the amino acid sequence of mature IL-1 alpha is conserved 60% to 70% and human IL-1 has been found to be biologically active on murine cell lines. Both forms of IL-1 bind to the same receptors,designated type I and type II. Recent evidence suggests that only the type I receptor is capable of signal transduction and that the type II receptor may function as a decoy,binding IL-1 and thus preventing binding of IL-1 to the type I receptor.Sample Type:Cell culture supernatants,serum,plasma,and tissueIntended Use:The Human IL-1alpha BioAssay ELISA Kit is an enzyme-linked immunosorbent assay for the quantitative detection of Human IL-1alpha concentrations in cell culture supernatants,serum,plasma,and tissue.Sensitivity:2pg/mlRange:3.9-250pg/mlSpecificity:Recognizes human IL-1alpha.Sample Volume:100ul/wellTest Principle:This assay employs the Sandwich immunoassay technique. An anti-h IL-1alpha monoclonal coating antibody is adsorbed onto microwells. IL-1alpha 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-1alpha antibody is added and binds to IL-1alpha captured by the first antibody. Following incubation unbound Biotinylated anti-h IL-1alpha antibody is removed during a wash step. A Streptavidin-HRP is added and binds to Biotinylated anti-h IL-1alpha antibody. Following incubation unbound Streptavidin-HRP is removed during a wash step. A colored product is formed in proportion to the amount of IL-1alpha 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-1alpha standard dilutions and IL-1alpha 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.