Preparation of monoclonal antibodies against neutrophil gelatinase-associated lipocalin (NGAL) and development of an antibody-based chemiluminescence immune quantification assay / 中国生化药物杂志

ABSTRACT

Objective To obtain monoclonal antibodies ( mAbs ) against neutrophil gelatinase-associated lipocalin ( NGAL ) and a chemiluminescense immune quantification assay based one paired mAbs.Methods Six-to-eight weeks old female BALB/c mice were immunized with the purified recombinant human NGAL antigen( rhNGAL) that was produced by the Escherichia coil expression system.The spleen was fused with hybridoma for screening anti-NGAL monoclonal antibodies by indirect ELISA.Western blot was implemented to identify the reactivity with native NGAL. Results The rhNGAL antigen was found to form disulfide cross-linked dimers and present excellent immunogenicity.The reaction titer of the immune serum of NGAL immunized mice was about 106.Thirty mAbs were screened by indirect ELISA, hereinto;the EC50 values of mAb23C12 and 38D10 were 0.034 g/mL, 0.022 g/mL respectively.The antibodies pair, 38D10/23C12-SAE labeled with AcridiniumEster(AE), were shown to work well in chemiluminescense immune response quantitative detection which was screened by NGAL standardand clinical urine samples.This detection can resolve positive and negative samples with a statistically significant difference (P<0.0001).And the correlation coefficient R2between NGAL quantitative results and that of the Abbott's NGAL chemiluminescence immune assay kit was greater than 0.97.The detection linear range was 10-1500 ng/mL, analytical sensitivity of the method was 0.63 ng/mL.Conclusion Highly purified rhNGAL antigen and specific anti-NGAL monoclonal antibodies are generated in this study.The detection capability of method is comparable with that of the international commercial kit.