Cloning of human plasminogen activator inhibitor-1(PAI1)gene and preparation of its monoclonal antibodies as well as its application in detection of PAI1 expression in breast cancer cells / 中华检验医学杂志

ABSTRACT

Objective To clne huma PAIl gene and prepare its monoclonal antibodies(McAbs) for determination of its expression in breast cancer cells.Methods Human PAI1 gene eDNA was amplified by RT-PCR from human breast cancer cell line MDA231 and inserted into the prokaryotic expression vector, which expressed fusion protein of MS2-PAI1 in E.coli.Fusion protein of MS2-PAI1 was purified and used for immunizing BALB/C mouse.Traditional hybridoma technology was used to produce hybridoma cells for preparation of monoclonal antibodies.Western blot and immunohistochemistry were used to detect PAI1 expression in breast cancer.Results The 1209 bp full PAI1 gene was cloned.The two hybridoma cell lines that secreted specific monoclonal antibodies against human PAI1 were identified by ELISA.The immunoglobulin subclasses of the McAbs were IgG1.The McAbs can specifically recognize PAI1 but not other proteins.Western blot showed that the McAbs against PAI1 can specifically react with MS2-PAI1 fusion protein and endogenous proteins in cells.The positive reaction was found in breast cancer cell line MDA231 and breast cancer tissues by immunochemical staining.Conclusions The McAbs against human PAI1 are successfully prepared by hybridoma technology with MS2-PAI1 fusion protein expressed in E.coll.It has been shown that PAI1 can be expressed in MDA231 and breast cancer tissues.The McAbs against PAI1 could be a useful tool for the further study of the human PAI1 functions and detection of clinical tumor samples.