Preparation of monoclonal antibody against human tissue kallikrein and development of an ELISA kit

Abstract

Objective To prepare monoclonal antibody(McAb) against human tissue kallikrein (HK) and develop an ELISA kit allows for the in vitro quantitative determination of human tissue kallikrein in urine. Methods To generate a monoclonal antibody specific for TK, the synthetic TK peptide consisting of 12 amine acids(12P), was fused to keyhole limpet hemocyanin(KLH) and used for immunization. Using hybridoma screening, monoclonal secreting cell lines were identified and used to generate ascites in BALB/c mouse. Antibody was purified by affinity column chromatography. 12% SDS-PAGE and Western blot were used to visualize the purified antibody. This kit employs indirect competitive ELISA technique and BiotinAvidin System. 12P was fused to bovine serum albumin(BSA) and has been pre-coated onto a microplate at first. Standards and samples were added to the appropriate microplate wells with a biotin-conjugated McAb croplate well. A TMB substrate solution is added to each well. The enzyme-substrate reaction is terminating by the addition of a sulphuric acid solution and the color change is measured spectrotometrically at a wavelength of 450 nm. The concentration of tissue kallikrein in the samples is then determined by comparing the O.D. of the samples to the standard curve. Results 8 hybridoma cell lines secreting mAbs special to HK,SDS-PAGE and Western blot demonstrated successful preparing and purification of McAb( 100% ). The linearity of this ELISA kit is demonstrated(r =0. 990). The range of detection of the assay is 0.008 μg/ml to 0. 5 μg/ml. The assay remained stable, with no change in the values measured, over five cycles of freezing and thawing. Conclusion 8 McAbs against HK have been prepared successfully and possess high titer and specificity. The development of an ELISA kit for detecting HK can meet the needs of detection of HK in urine samples. Key words: Human tissue kallikrein; Monoclonal antibody; ELISA