Li S, Plouffe BD, Belov AM, Ray S, Wang X, Murthy SK, Karger BL, Ivanov AR.
Mol Cell Proteomics. 2015 Mar 9. pii: mcp.M114.045724.
Isolation and molecular characterization of rare cells (e.g. circulating tumor and stem cells) within biological fluids and tissues has significant potential in clinical diagnostics and personalized medicine. The present work describes an integrated platform of sample procurement, preparation and analysis for deep proteomic profiling of rare cells in blood. Microfluidic magnetophoretic isolation of target cells spiked into 1 mL of blood at the level of 1,000-2,000 cells/mL, followed by focused acoustics-assisted sample preparation has been coupled with one-dimensional PLOT-LC-MS methodology. The resulting zeptomole detection sensitivity enabled identification of approximately 4,000 proteins with injection of the equivalent of only 100-200 cells per analysis. The characterization of rare cells in limited volumes of physiological fluids is demonstrated by the isolation and quantitative proteomic profiling of first MCF-7 cells spiked into whole blood as a model system and then two CD133+ endothelial progenitor and hematopoietic cells in whole blood from volunteers.http://www.mcponline.org/content/early/2015/03/09/mcp.M114.045724.long