Analysis of gamma-globulin mobility on routine clinical CE equipment: exploring its molecular basis and potential clinical utility

Electrophoresis. 2009 Aug;30(15):2617-23. doi: 10.1002/elps.200900054.

Abstract

A study was conducted on the variability of gamma-globulin mobility in serum protein electrophoresis and its molecular basis. We found that the migration time of gamma-globulins can be reproducibly determined (CV=1.1%) on clinical CE equipment. Moreover, we found a significant difference (p<0.001) in the migration of gamma-globulins between chronic liver disease patients (n=98) and a healthy reference group (n=47). Serum immunoglobulins were purified from these patients' sera using protein L-agarose and their glycosylation was studied using CE on a DNA sequencer. This glycomics approach revealed that several non-sialylated N-glycans show a moderate Pearson correlation coefficient (r=0.2-0.4) with the migration time of gamma-globulins. Their sialylated structures correlate negatively (r=-0.2 to -0.3). Immunoglobulins are significantly more sialylated in the healthy reference group compared with the patients (p<0.001). We estimated that sialylation heterogeneity contributes about 36% to the molecular variance (carbohydrates and amino acid composition) that affects the electrophoretic mobility of immunoglobulins. This is the first report on the migration time of gamma-globulins on a clinical CE instrument and its potential clinical value to the routinely analyzed serum protein CE profiles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / blood
  • Chronic Disease
  • Electrophoresis, Capillary / methods*
  • Female
  • Glycosylation
  • Humans
  • Liver Diseases / blood
  • Male
  • Statistics, Nonparametric
  • gamma-Globulins / chemistry
  • gamma-Globulins / isolation & purification*

Substances

  • Biomarkers
  • gamma-Globulins