Epidermal Growth Factor, Human (EGF), BioAssay(TM) ELISA Kit

Epidermal growth factor (EGF), a polypeptide mitogen, was first observed in 1959 by Cohen and Levi-Montalcini while studying Nerve Growth Factor (NGF) in snake venom extracts.1 It was subsequently isolated and purified from mouse submandibular glands. When injected into new-born mice this new factor caused precocious eyelid opening and incisor eruption.2,3 EGF was further purified, based on its ability to induce the proliferation of basal skin cells.4 Also, a potent inhibitor of gastric acid secretion was identified and isolated from the urine of a pregnant women, and named human b-urogastrone. It was shown that this protein was very similar to purified human EGF.5,6 This EGF enzyme-linked immunosorbent assay (ELISA) applies a technique called a quantitative sandwich immunoassay. The microtiter plate provided in this kit has been pre-coated with a monoclonal specific for EGF. Standards or samples are then added to the appropriate microtiter plate wells and incubated. EGF if present, will bind and become immobilized by the antibody pre-coated on the wells. The microtiter plate wells are thoroughly washed to remove unbound EGF and other components of sample. In order to quantitate the amount of EGF present in the sample, a standardized preparation of horseradish peroxidase (HRP)-conjugated polyclonal antibody specific for EGF is added to each well to "sandwich" the EGF immobilized during the first incubation. The microtiter plate then undergoes a second incubation. The wells are thoroughly washed to remove all unbound HRP-conjugated antibodies and a TMB (3,3'5,5' tetramethyl-benzidine) substrate solution is added to each well. The enzyme (HRP) and substrate are allowed to react over a short incubation period. Only those wells that contain EGF and enzyme-conjugated antibody will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of a sulfuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450nm