[Enzyme-linked immunosorbent assay for serum prostate specific antigen (PSA) using monoclonal antibodies]

Prostate specific antigen (PSA) is a widely used marker for screening and monitoring prostate cancer. However, different commercial immunoassays, often give different PSA values for the same patient sample. We produced 59 monoclonal antibodies against human PSA. Two monoclonal antibodies (No. 54 and No. 47) against PSA were used to develop one-step ELISA for serum PSA. In the combination of these two antibodies, incubation for more than 30 minutes gave an equimolar response to both free-PSA and PSA complexed to alpha 1-antichymotrypsin. The procedure is simple, and the method is specific and reproducible. The average recovery for serum sample was 90-107%.