Description
Introduction: Eosinophil cationic protein (ECP) is a small, basic protein found in the matrix of the eosinophil's large specific granule that has cytotoxic, helminthotoxic, and ribonuclease activity, and is a member of the ribonuclease multigene family. Human eosinophil granules contain several basic proteins including ECP, eosinophil-derived neurotoxin (EDN) and major basic protein (MBP). ECP and MBP are potent helminthotoxins while EDN is less so. Both ECP and EDN possess neurotoxic and ribonuclease activities
Principle of the Assay: The microtiter plate provided in this kit has been pre-coated with an antibody specific to ECP. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated antibody preparation specific for ECP 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 ECP, 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 ECP in the samples is then determined by comparing the O.D. of the samples to the standard curve