Purification and immunoreactivity of monoclonal antibodies against myeloma-lambda chain.

In this study, two murine IgM-monoclonal antibodies (IgM-McAbs) against lambda chain of myeloma protein from hybridoma ascites were purified by Sephadex G200 chromatography. The eluate of the first peak on absorption at 280 nm formed one precipitation band with rabbit anti-mouse IgM or anti-mouse immunoglobulin in agar gel double diffusion test; it also formed a detectable precipitation line in the IgM reaction area in immunoelectrophoresis. These findings showed that the eluate of the first peak on absorption at 280 nm contained purified IgM-McAbs. It was found in indirect ELISA that the immunoreactivity of the eluate of the first peak was four to five fold higher than that of the original ascites with equimolar protein concentration. Double antibody sandwich ELISA analyses of the immunoreactivity of HRP-conjugated IgM-monoclonal antibodies with lambda chain denoted that the purified IgM-McAb-HRP-conjugate might be of practical value in quantitative as well as qualitative assay of lambda chains.