Description
Introduction: Interleukin 5 or IL-5 is an interleukin produced by T helper-2 cells and mast cells. Its functions are to stimulate B cell growth and increase immunoglobulin secretion. It is also a key mediator in eosinophil activation. IL-5 expression is regulated by several transcription factors including GATA-3. Interleukin-5 has long been associated with several allergic diseases including allergic rhinitis and asthma where a large increase in the number of circulating, airway tissue, and induced sputum eosinophil numbers has been observed. Given the high concordance of eosinophils and, particularly, allergic asthma pathology, it has been widely speculated that eosinophils have an important role in the pathology of this disease.
Principle of the Assay: The microtiter plate provided in this kit has been pre-coated with an antibody specific to IL-5. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated polyclonal antibody preparation specific for IL-5 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 IL-5, 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 IL-5 in the samples is then determined by comparing the O.D. of the samples to the standard curve