Diphtheria ELISA kit description:

For the quantitative determination of serum antibody response to diphtheria toxoid. Diphtheria is an acute communicable disease, caused by Corynebacterium diphtheriae. The signs and symptoms of infection are a pharyngeal membrane, sore throat, dysphasia, malaise, headache, and nausea. Death may result from respiratory obstruction by the membrane or myocarditis from the toxin. Although diphtheria is still a serious problem in many underdeveloped countries, active immunizations in many developed countries have helped to decrease the number of reported cases of diphtheria infection. Recent epidemics in eastern Europe and Russia, combined with low levels of protective diphtheria antitoxin (DAT) in adult populations, have caused concern that outbreaks of diphtheria could occur in developed countries. A study in northern Europe reported findings of 26% of the surveyed population being below the minimum protective level of 0.01 IU/ml. A number of methods are available for evaluating the DAT levels in body fluids. Passive hemagglutination (PHA) is widely used, but has been found to be often discrepant, rendering interpretation of the PHA test very risky for the individual patient. The use of enzyme-linked immunosorbent assays for determining DAT levels has been evaluated as simple to perform, economical, and precise. Thus the ELISA is a very practical method for seroepidemiological purposes. The micro test wells are coated with diphtheria toxoid antigen. During the first incubation with the diluted patients’ sera, any antibodies which are reactive with the antigen will bind to the coated wells. After washing to remove the rest of the sample, the Enzyme Conjugate is added. If antibodies have been bound to the wells, the Enzyme Conjugate will then bind to these antibodies. After another series of washes, a chromogen (tetramethylbenzidine or TMB) is added. If the Enzyme Conjugate is present, the peroxidase will catalyze a reaction that consumes the peroxide and turns the chromogen from clear to blue. Addition of the Stop Solution ends the reaction and turns the blue color to a bright yellow color. The reaction may then be read with an ELISA reader.