Study of uroproteins in myeloma patients by sodium dodecyl sulfate-polyacrylamide gel electrohporesis (SDS-PAGE).

Samples of the urine of 10 myeloma patients with proteinuria were examined by SDS-PAGE. Light chain proteins of Bence Jones (B.J.) type were excreted by 7 patients as monomer (m.w. 20--26.5 x 10(3) Dalton, by 2 patients as a mixture of monomer and dimer and by one patient as dimer. By two-dimensional electrophoresis in SDS-PAG and subsequent electrophoresis in agarose containing kappa and lambda chain specific antibodies the immunological identity of monomeric and dimeric B.J. protein of one patient has been shown. The two-dimensional analysis has been proven a valuable procedure in cases with the excretion of complete monoclonal protein and B.J. protein at the same time.