Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) is a
powerful tool for the visualization of proteins in tissues and has demonstrated considerable
diagnostic and prognostic value. One main challenge is that the molecular identity of such
potential biomarkers mostly remains unknown. We introduce a generic method that removes
this issue by systematically identifying the proteins embedded in the MALDI matrix using a
combination of bottom-up and top-down proteomics. The analyses of ten human tissues lead …