Discrimination of monoclonal antibodies by biotin-avidin enzymeimmunoassay.

A new method for the discrimination of epitopes of monoclonal antibodies by biotin-avidin enzymeimmunoassay was developed. The principle of this method was as follows: Several monoclonal antibodies reacted with one antigen were defined. After incubation of one non-biotinylated monoclonal antibody in the antigen coated polystylene plate, biotinylated another monoclonal antibody was added and incubated. After washing, peroxidase conjugated avidin was reacted. Finally, peroxidase activity was assayed using O-phenylenediamine as substrate containing H2O2. As the results, it was probable that the non-biotinylated monoclonal antibody was different from the biotinylated monoclonal antibody when peroxidase activity could be detected. On the other hand, it was suggested that the non-biotinylated antibody had a same epitope of the biotinylated antibody, or the antigenic determinants which were recognized with both monoclonal antibodies were very closed when peroxidase activity couldn't be detected.This method was very easy and safe to handle comparing with the method using radioactive compounds. The biotinylated antibodies, furthermore, were stable over one year when they were stocked at 4°C.