A Method for Analysis of the Low-Molecular-Weight Proteomes of Tissues for Possible Use in Biomarker Discovery

摘要

The search for low molecular weight peptide biomarkers is a potentially powerful method for characterizing, diagnosing, and predicting a variety of diseases. Serum proteomics has become the favored area for biomarker research, with widely developed and detailed methodologies. While blood serum is an invaluable source of biomarkers, tissue may also prove to be valuable, yet little has been published on the low molecular weight tissue proteome. As a test of feasibility of this low molecular weight tissue proteomic approach, a survey of peaks in one 2 min fraction of the cLC eluate was undertaken across five tissue types. On average ～4000-5000 peptides were observed for any given tissue. Several peaks were unique to only one tissue type. As an example of this, one peak unique to spleen was selected from the overlays, fragmented by CID, and identified as a peptide derived from desmin, a known protein marker of spleen cells.