[Abundant protein' depletion in search of biomarkers]

Using a simple two step procedure, we simultaneously removed the two most abundant components of serum, albumin and immunoglobulins, and enriched for a subset of glycoproteins. Protein profiles analyzed from treated samples were different in composition and abundance when compared to unprocessed serum. The complexity of the protein sample was reduced and the problems associated with the dynamic range were mitigated, allowing for a greater protein load to be applied to the gel. This resulted in the detection of a greater number and variety of proteins. We subsequently tested the suitability of this procedure for biomarker discovery using 12 samples from diseased and non-diseased patients. We found that protein profiles from this enriched fraction were different between the two groups, suggesting that such an approach can assist with new biomarker discovery efforts and the identification of biomarker candidates. Finally, considerations for the translation of biomarkers, identified in such a manner, to a clinically useful assay, are discussed.