Most complete human blood-plasma proteome to date
Pacific Northwest National Laboratory researchers have identified an astounding 1,700 confidently identified distinct proteins (excluding immunoglobulin proteins) in human blood plasma, representing a critical step towards cataloging biological markers for the early diagnosis of cancer and other diseases. Confidence in protein identifications was determined by utilizing the normalized elution time search criteria and a false positive identification strategy, both of which were recently developed at PNNL.
This large coverage is important because proteins from distressed cells in tissues are commonly leaked into the blood stream, and identification of these proteins in the blood may serve as a method for detecting the early onset of disease. The approach uses high resolution liquid chromatography (LC) combined with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry instrumentation developed in the Environmental Molecular Sciences Laboratory (EMSL)—detecting as little as 10 zeptomoles (or 6,000 molecules). In 2003, the LC-FTICR, was named one of the 100 top inventions of the year by R&D Magazine.