MALDI MS imaging as a powerful tool for investigating synovial tissue

To identify and image protein biomarker candidates in the synovial tissue of patients with rheumatoid arthritis (RA) and patients with osteoarthritis (OA).A novel matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS) technique was applied to the analysis of synovial tissue. Patients were classified according to the American College of Rheumatology (ACR) criteria for RA. Frozen sections were stained to obtain morphological data. Serial sections were desiccated, and spotted with matrix for MALDI analysis. Ions generated by laser irradiation of the tissue were separated in time, based on their m/z ratio, and were subsequently detected. IMS was used in a 'profiling…