Detection and identification of monoclonal gammopathies by capillary electrophoresis

Abstract

Capillary electrophoresis (CE) and immunosubtraction capillary electrophoresis (IS-CE) were compared with the conventional methods agarose gel electrophoresis (AGE) and immunofixation electrophoresis (IFE) for detection and identification of paraproteins. In total, 74 paraproteins out of 468 serum samples were detected by both methods. Seventy-three monoclonal bands with concentrations ranging from 0.6 to 50.9 g/L were detected by the routine method. With CE, 70 paraproteins were detected and quantified on the electropherogram. Four paraproteins were not detected by CE; three of these were IgG (0.6, 1.1, and 2.2 g/L, respectively), and one was a IgM paraprotein (20.3 g/L) that could be visualized by minor changes in the running conditions. In comparison with IFE, 69 paraproteins were typed identically using IS-CE; only one paraprotein (IgMκ, 14.9 g/L) could not be identified. On the other hand, a monoclonal IgA band that had not been detected by AGE was identified by CE and IS-CE. We conclude that, in general, CE could be a useful method for detection of paraproteins and that IS-CE is a good alternative to IFE. Additional studies are required to investigate the ionic strength and pH of the running buffer, because these prove to be the most crucial factors for routine CE separation of paraproteins.

Detection of biclonal gammopathy by capillary zone electrophoresis in a cat and a dog with plasma cell neoplasia

“…Moreover, better resolution of different fractions is obtained by CZE compared with other techniques, especially when large and poorly defined spikes are present. 6 The higher resolution of CZE compared with CAE is emphasized in the 2 cases in this report in which 2 distinct paraproteins with similar migration patterns were produced, giving rise to a single large spike by CAE analysis. Rarely, paraproteins are not detected by CZE or AGE.…”

“…In a human study, both techniques showed higher sensitivity in detecting monoclonal spikes compared with standard CAE (98%, 93%, and 83% for CZE, AGE, and CAE, respectively) with similar specificity (91%, 91%, and 94%, respectively). Moreover, better resolution of different fractions is obtained by CZE compared with other techniques, especially when large and poorly defined spikes are present 6 . The higher resolution of CZE compared with CAE is emphasized in the 2 cases in this report in which 2 distinct paraproteins with similar migration patterns were produced, giving rise to a single large spike by CAE analysis.…”

“…10 CZE has been suggested as an alternative to conventional agarose gel electrophoresis (AGE) in separating human serum proteins because it permits fast protein separation with good resolution and requires a smaller sample volume. 6 When compared with AGE, similar sensitivity and specificity for detecting monoclonal spikes have been reported. 10,11 In a human study, both techniques showed higher sensitivity in detecting monoclonal spikes compared with standard CAE (98%, 93%, and 83% for CZE, AGE, and CAE, respectively) with similar specificity (91%, 91%, and 94%, respectively).…”

“…CZE is an analytical tool for separating molecules on the basis of size, electric charge, and hydrophobicity and has been used in human medicine to detect and separate hemoglobin variants, PCR products, and serum proteins. [6][7][8] In CZE ionic mobility is related to the charge:mass ratio, 8 and smaller or multiply charged anions are detected later than anions with a lower mobility. Analytes, including ions, drugs, and peptides, are seen as peaks as they pass through the detector.…”

“…CZE has been suggested as an alternative to conventional agarose gel electrophoresis (AGE) in separating human serum proteins because it permits fast protein separation with good resolution and requires a smaller sample volume 6 . When compared with AGE, similar sensitivity and specificity for detecting monoclonal spikes have been reported 10,11 .…”