title: Improvements of TArgeted multiplex mass spectrometry IMaging.
abstract: MALDI mass spectrometers have become popular tools for imaging histological sections. Currently this technology is primarily used for imaging naturally occurring molecules. Here we report on the improvement of TArgeted multiplex MS IMaging (TAMSIM) technology. For TAMSIM we attach photocleavable mass tags to antibodies. Staining histological sections is done analogously to standard immunohistochemical procedures with chemiluminescent or fluorescent detection with the sole difference that multiple antibodies each with a distinct mass tag are used in a single reaction. Mass tags are released from their respective antibodies by a laser pulse at 355 nm without added matrix. After scanning, MS images are created for each tag mass. The enhancements of TAMSIM presented here relate to four elements, the use of an improved generation of tags, their conjugation directly to primary antibodies, the comparison of fresh frozen sections with paraffin embedded ones for the TAMSIM imaging technology and finally, the increase of multiplex detection. Sections of healthy human pancreatic tissue were imaged to visualize different specific biomarkers (synaptophysin, chromogranin, insulin, calcitonin, somatostatin) in neuroendocrine cells of Langerhans islets. The aim was to localize these biomarkers on the tissue sections simultaneously.
authors.affiliation: CEA/Institut de Génomique-Centre National de Génotypage, Evry, France.
authors.forename: Gwendoline
authors.initials: G
authors.lastname: Thiery
authors.forename: Elsa
authors.initials: E
authors.lastname: Anselmi
authors.forename: Anne
authors.initials: A
authors.lastname: Audebourg
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Darii
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abarbri
authors.forename: Benoît
authors.initials: B
authors.lastname: Terris
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Tabet
authors.forename: Ivo G
authors.initials: IG
authors.lastname: Gut
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007801:Langerhans Cells / Q000378:metabolism; D010179:Pancreas / Q000166:cytology / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D046888:Tissue Array Analysis / Q000379:methods
chemical_list: D015415:Biomarkers