Quench me if you can: Alpha-2-macroglobulin trypsin complexes enable serum biomarker analysis by MALDI mass spectrometry

One of the main functions alpha-2-macroglobulin (A2M) in human blood serum is binding all classes protease . It known that trypsin , after such interaction, possesses modified proteolytic activity Trypsin first hydrolyzes two bonds A2M’s ‘bait region’, and peptide 705 VGFYESDVMGR 715 released from A2M. In this work, specifics A2M-trypsin interaction were used to determine A2M concentration directly using MALDI mass-spectrometry. Following exogenous addition vitro, was measured, its isotopically-labeled analogue ( 18 O), calculated. The optimized mass spectrometric approach verified a standard method for determination (ELISA) relevant statistical analysis methods. also shown trypsin’s presence can be analyze other proteins including potential biomarkers pathological processes. Thus, work describes promising biomarker technically extended several useful directions. • results release peptide. This detectable spectrometry. Peptide concentrations measured an analogue. developed cross ELISA. complexes wide range biomarkers.