Heparin chromatography to deplete high-abundance proteins for serum proteomics

BackgroundSerum is a very informative sample for disease diagnosis. However, a few of the high-abundance proteins existing in serum make the identification of disease-specific serum biomarkers extremely challenging using currently available technologies. A highly promising first step for most analytical approaches of serum is to deplete as many of the high-abundance proteins as possible.MethodsWe introduced the traditional method of heparin chromatography coupled with protein G sepharose to deplete the high-abundance proteins for serum proteomics.ResultsCompared with the multiple affinity removal system (MARS) column (a commercial version to deplete 6 major proteins in serum), heparin chromatography can deplete more high-abundance proteins in a single step, especially many high molecular-weight proteins. Using this simple and inexpensive method to pretreat serum for 2-DE analysis, more protein spots can be visualized. IgGs depletion by protein G sepharose can further enhance the resolution of the resulting serum proteome.ConclusionsHeparin chromatography coupled with protein G appears to be an efficient and economical strategy to pretreat serum for serum proteomics.