title: MALDI imaging mass spectrometry of N-linked glycans on formalin-fixed paraffin-embedded murine kidney.
abstract: Recent developments in spatial proteomics have paved the way for retrospective in situ mass spectrometry (MS) analyses of formalin-fixed paraffin-embedded clinical tissue samples. This type of analysis is commonly referred to as matrix-assisted laser desorption/ionization (MALDI) imaging. Recently, formalin-fixed paraffin-embedded MALDI imaging analyses were augmented to allow in situ analyses of tissue-specific N-glycosylation profiles. In the present study, we outline an improved automated sample preparation method for N-glycan MALDI imaging, which uses in situ PNGase F-mediated release and measurement of N-linked glycans from sections of formalin-fixed murine kidney. The sum of the presented data indicated that N-glycans can be cleaved from proteins within formalin-fixed tissue and characterized using three strategies: (i) extraction and composition analysis through on-target MALDI MS and liquid chromatography coupled to electrospray ionization ion trap MS; (ii) MALDI profiling, where N-glycans are released and measured from large droplet arrays in situ; and (iii) MALDI imaging, which maps the tissue specificity of N-glycans at a higher resolution. Thus, we present a complete, straightforward method that combines MALDI imaging and characterization of tissue-specific N-glycans and complements existing strategies.
authors.affiliation: Adelaide Proteomics Centre, School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, 5005, Australia.
authors.forename: Ove J R
authors.initials: OJ
authors.lastname: Gustafsson
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Briggs
authors.forename: Mark R
authors.initials: MR
authors.lastname: Condina
authors.forename: Lyron J
authors.initials: LJ
authors.lastname: Winderbaum
authors.forename: Matthias
authors.initials: M
authors.lastname: Pelzing
authors.forename: Shaun R
authors.initials: SR
authors.lastname: McColl
authors.forename: Arun V
authors.initials: AV
authors.lastname: Everest-Dass
authors.forename: Nicolle H
authors.initials: NH
authors.lastname: Packer
authors.forename: Peter
authors.initials: P
authors.lastname: Hoffmann
mesh_terms: D000818:Animals; D005557:Formaldehyde / Q000737:chemistry; D007668:Kidney / Q000737:chemistry*; D051379:Mice; D016612:Paraffin Embedding; D011134:Polysaccharides / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D016707:Tissue Fixation
chemical_list: D011134:Polysaccharides; D005557:Formaldehyde