ANTI-ENZYME ANTIBODY IMMUNOASSAY

An immunoassay utilizing the inhibition or inactivation of a signal generating molecule to reduce a controlled baseline signal to a lower level of signal corresponding to the amount of analyte present in the sample. one embodiment is a heterogeneous enzyme immunoassay, preferably using monoclonal antibodies wherein an insolublized first antibody binds to an antigen analyte of interest. A second and third antibody, which themselves have been conjugated together, are added so that the second antibody complexes preferentially with the antigen. Then an active enzyme and its specific substrate are added to the complex, simultaneously for example, and enzyme will be bound preferentially to the third antibody which exerts an inhibitory influence on the enzyme. The resultant decrease in enzyme activity is measured and the relative amount of antigen in the sample is calculated.