【DESCREPTION】Tumor necrosis factor alpha (TNF-α), also known as cachectin and TNFSF1A, is an adipokine involved in systemic inflammation and is a member of a group of cytokines that stimulate the acute phase reaction. It is produced chiefly by activated macrophages, although it can be produced by many other cell types such as CD4+ lymphocytes, NK cells, neutrophils, mast cells, eosinophils, and neurons. It functions as a multipotent modulator of immune response and further acts as a potent pyrogen. TNF-α circulates throughout the body responding to stimuli (infectious agents or tissue injury), activating neutrophils, altering the properties of vascular endothelial cells, regulating metabolic activities of other tissues, as well as exhibiting tumoricidal activity by inducing localized blood clotting. TNF-α may play a significant role in the pathogenesis of inflammatory disease of the joints and other tissues. Recently, a growing body of information has pointed to a role for TNF-α in the pathogenesis of AIDS. Measurement of TNF-α levels has also been shown to be useful in transplant research.
【PRINCIPLE OF THE ASSAY】This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for human TNF-α has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and TNF-α present is bound by the immobilized antibody. After washing away any unbound substances, a biotin-linked detect antibody specific for TNF-α is added to the wells. Following a wash to remove any unbound antibody-biotin reagent, streptavidin-HRP is added. After washing, amplification reagent is added to the wells. Following incubation any unbound substances is removed during a wash step and streptavidin-HRP is added. After washing, substrate solution is added to the wells and color develops in proportion to the amount of TNF-α bound in the initial step. The color development is stopped and the intensity of the color is measured.
【板间变异系数】4.1% -4.8 %
【板内变异系数】5.4 % - 7.0%