Chemiluminescence Immunoassay for Quantitative Analysis of Prostate Specific Antigen Complexed to α1-Antichymotrypsin in Human Serum

Eight mouse hybridoma cell lines which stably secreted monoclonal antibodies (McAbs) against human prostate. specific antigen-alpha 1-antichymotrypsin complex (PSA-ACT) were obtained through hybridoma technique. After purification, the immunological characters of 8 McAbs were identified and classified by epitopes analysis through indirect enzyme. linked immunosorbent assay (ELISA). A pair of McAbs was chosen from above 8 McAbs, based on which a highly sensitive, simple and rapid chemiluminescence enzyme immunoassay (CLEIA) was developed for determination of PSA-ACT in human serums using the lumino-H2O2 reaction catalyzed by horseradish peroxidase (HRP) as the chemiluminescence system. Several experiment factors such as coating buffer, coating concentration, dilution ratio of PSA-ACT-HRP complex, incubation time, immunoreaction protocol and chemiluminescence reaction time were optimized. The results showed that the linear range of the proposed method for PSA-ACT determination was 0-40 ng/mL (R-2 = 0. 9943), with the detection limit of 0. 53 ng/mL. The inter. assay relative standard deviations (RSDs) were 4. 6%-6. 6%, and intra. assay RSDs were 5. 7%-8. 0%. The recoveries of PSA-ACT at three spiked levels in serum samples were 95. 4%-104. 2%. The proposed method exhibited a cross. reactivity of 0. 6% with free. PSA. The proposed method is stable, sensitive, rapid and simple, and provides a foundation for the development of PSA-ACT CLEIA kit and shows great value in clinical auxiliary diagnosis of prostate cancer.