DATE: January 18, 2018
TIME: 7:00 AM PST, 10:00 AM EST

Tandem mass spectrometry (MS) is advertised as a detection and quantification method that alleviates most of the flaws inherent to immunoassays. In 2012, MS-based targeted proteomics was declared method of the year as it allows quantification of either specific proteoforms* or specific subsets of proteins of interest. MS-based targeted proteomics can also be used in a highly multiplexed format and allows for precise molecular characterization of the measurands.

Targeted proteomics is frequently performed using a typical MRM-workflow consisting of five steps: defining the protein set of interest based on the clinical or biological question; selecting appropriate peptides which are proteotypic and have suitable LC/MS properties; selecting transitions based on their intensity; analytically validating the transitions to prevent interferences and quantitating the specific protein(s) by calibration using either value-assigned peptide or matrix-based calibrators.

The most critical step for absolute quantification of proteins in body fluids is the sample preparation, and more specifically the (trypsin) digestion step.

MS-based targeted proteomics will be presented which have great potential as an alternative technology to antibody-based protein assays in hypothesis driven clinical trials. Our research has shown that from a standardization viewpoint, major advantages of MRM coupled to MS are its potential to unequivocally measure specific molecular entities, to assess directly the compounds of interest, and the lack of non-selectivity if transitions are well selected.

Learning Objectives:

• Understanding test purpose and test role of MS-based protein tests
• Understanding a targeted proteomics workflow for quantification of MS-based protein tests, as well as the critical steps for standardization
• Understanding the challenges which have to be overcome during development and routine operation of MS-based protein tests.

For Research Use Only. Not for use in diagnostic procedures.