[Development and application of monoclonal antibodies against human free prostate specific antigen(f-PSA)].

Objective Construction of monoclonal antibody cell lines against human free prostate specific antigen (f-PSA), and establish double antibody sandwich CLIA for human f-PSA. Methods Two hybridoma cell lines secreting anti-f-PSA mAb were obtained by hybridoma technique. The cell lines were expanded by spinner bottles and purified by affinity purification, from which the antibodies were tested for antibody titers, specificity, epitopes by ELISA and affinity by surface plasmon resonance. Establishment, analysis and performance evaluation of a double mAbs sandwich CLIA system using standard curve quantitative method. In total 426 (130 gray area) clinical specimens were used for system comparison between our assay and Roche f-PSA assay. Results anti- f-PSA(f-10-1, f-14-1) mAbs were obtained. The CLIA system with detection range of 0.1-30 ng/mL, sensitivity of 0.05 ng/mL, relative detection deviation of ±5% and not cross-react with the tumor marker AFP, CEA and c-PSA. The correlation coefficient of our reagent with Roche's was 0.99. The positive coincidence rate, negative coincidence rate and total coincidence rate of gray area specimens were all higher than 90%. Conclusion mAbs against human f-PSA were successfully prepared, and the double mAbs sandwich CLIA for specific quantitative detection of human f-PSA was established.

[Preparation and characterization of monoclonal antibodies against human CA50 and establishment of chemiluminescence immunoassay system].

OBJECTIVE: To prepare the anti-human carbohydrate antigen 50(CA50) monoclonal antibody (mAb), characterize its immunological features and establish a chemiluminescence immunoassay system with it. METHODS: BALB/c mice were immunized with human CA50 antigen for preparing mAb using hybridoma technique. Stable anti-CA50-secreting hybridoma cell lines were obtained after screening. The mAbs were purified using protein A after expanding culture. The chemiluminescence immunoassay system was established and evaluated in its linear range, accuracy, sensitivity, reproducibility, and the blood samples were tested with it. RESULTS: Four hybridoma cell lines were obtained respectively and their titers were above 1:10(8). Anti-CA50 mAbs nearly had no cross-reaction with CA125, CA153, CA199 and CA724. The linear detection of the chemiluminescence immunoassay system covered a range 0-500 U/mL. The recovery rate for accuracy was 107.08% and its sensitivity was 0.83 U/mL. The assay was highly repeatable [coefficient of variation (CV)<10%]. The correlation coefficient with the test of reference reagent was 0.96. CONCLUSION: The monoclonal antibodies against human CA50 had been screened and a chemiluminescence immunoassay system for human CA50 detection had been established successfully.

[Preparation and characterization of the monoclonal antibodies against human CA19-9 and establishment of a sandwich CLIA system].

OBJECTIVE: To prepare the monoclonal antibodies (mAbs) against human carbohydrate antigen 19-9 (CA19-9) and establish a double-antibody sandwich chemiluminescent immunoassay (CLIA) detection system for CA19-9 in the human serum. METHODS: BALB/c mice were immunized with human CA19-9 antigen. The mAbs were obtained by hybridoma technique. The purity, titer, specificity and pairing of the mAbs were characterized and the sandwich CLIA system was established. The system was evaluated in its accuracy, limit of detection, linearity and repetitiveness after optimization of coating buffer, coating concentration and pipetting mode, and the serum sample was tested with it. RESULTS: Four mAbs named #1-1, #2-1, #3-1 and #4-1 were obtained against human CA19-9. The titers of the anti-CA19-9 mAbs were above 10(-8). The mAbs had nearly no cross-reaction with CA125, CA15-3 and CA72-4. The double-antibody sandwich CLIA system was established by #3-1 mAb and #2-1 mAb-HRP. After optimization, its property was detection range of 0-1 000 U/mL, limit detection of 2.0 U/mL, linear correlation coefficient of 0.9999. The results which were contrasted with Roche test showed that: Kappa>0.75, r(correlation coefficient)>0.9. CONCLUSION: The mAbs against human CA9-9 have been prepared and a sandwich CLIA system for detecting CA19-9 in the human serum has been established successfully.

[Preparation and characterization of the monoclonal antibodies against human CA15-3 and establishment of a sandwich CLIA system].

OBJECTIVE: To prepare the monoclonal antibodies (mAbs) against human carbohydrate antigen 15-3 (CA15-3) and establish a double-antibody sandwich chemiluminescent immunoassay (CLIA) system for detecting CA15-3 in the human serum. METHODS: BALB/c mice were immunized with human CA15-3 antigen. Spleen cells of the immunized mice were fused with Sp2/0 cells and the positive hybridoma cells were selected and subcloned. The supernatant was taken for purify mAbs using protein A chromatography. The purity, titer, epitope and subtype of the mAbs were characterized and the sandwich CLIA system was established. The system was evaluated in its accuracy, limit of detection, linearity, repetitiveness and specificity. RESULTS: Five hybridoma cell lines named #3-1-3, #5-2-2, #11-2-2, #12-1-3 and #16-1-3 were obtained respectively, which are of strong positive signal and high secretion. The titers of the mAbs secreted by these hydridomas were above 10(-8); g/mL. All of the mAbs expressed κ light chains, and their heavy chains were as follows: #3-1-3 mAb had IgG2a, #5-2-2 mAb and #12-1-3 mAb had IgG2b, #11-2-2 mAb and #16-1-3 mAb had IgG3. The double-antibody sandwich CLIA system had a good linear relationship between 0.59 U/mL and 300 U/mL. The recovery rate for accuracy was 97.45% and the limit of detection was 0.59 U/mL. The assay was highly linear (correlation coefficient 0.9978) and highly repeatable [coefficient of variation (CV) <10%]. This CLIA system was also highly specific without cross-reactivity to the tumor marker AFP, CEA, CA50, CA19-9 and CA72-4. CONCLUSION: The mAbs against human CA15-3 have been prepared and a sandwich CLIA system for detecting CA15-3 in the human serum has been established successfully, which provides a basis for CA15-3 quantification and clinical application.