Description
Introduction: Interferons (IFNs) are natural cell-signaling proteins produced by the cells of the immune system of most vertebrates in response to challenges such as viruses, parasites and tumor cells. Interferons belong to the large class of glycoproteins known as cytokines. Interferons are produced by a wide variety of cells in response to the presence of double-stranded RNA, a key indicator of viral infection. Interferons assist the immune response by inhibiting viral replication within host cells, activating natural killer cells and macrophages, increasing antigen presentation to lymphocytes, and inducing the resistance of host cells to viral infection. There are three major classes of interferons that have been described for humans according to the type of receptor through which they signal: type I, II and III IFNs.
Principle of the Assay: The microtiter plate provided in this kit has been pre-coated with an antibody specific to IFN-beta. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated antibody preparation specific for IFN-beta and Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Then a TMB (3,3',5,5' tetramethyl-benzidine) substrate solution is added to each well. Only those wells that contain IFN-beta, biotin-conjugated antibody and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450 nm +/- 2 nm. The concentration of IFN-beta in the samples is then determined by comparing the O.D. of the samples to the standard curve