title: Spatially-resolved protein surface microsampling from tissue sections using liquid extraction surface analysis.
abstract: Tissue microenvironment characterization presents a challenge for a better understanding of the full complexity of a pathology. Unfortunately, making a precise "picture" of the disease needs an efficient microsampling method coupled to an accurate localization for performing region-dependent proteomics. Here, we present a method that enables rapid and reproducible extraction of proteins from a tissue section to analyze a specific region at a millimeter scale. The method used a liquid-microjunction extraction with conventional detergent solution for proteomics analysis. We successfully performed immunoblotting experiments and showed the possibility to retrieve and identify more than 1400 proteins from a 1-mm diameter spot size on tissue sections with a high degree of reproducibility both qualitatively and quantitatively. Moreover, the small size of the extracted region achieved by this sampling method allows the possibility to perform multiple extractions on different tissue section points. Ten points on a sagittal rat brain tissue section were analyzed and the measured proteins clearly distinguished the different parts of the brain, thus permitting precise functional mapping. We thus demonstrate that with this technology, it is possible to map the tissue microenvironment and gain an understanding of the molecular mechanisms at millimeter resolution.
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Maxence
authors.initials: M
authors.lastname: Wisztorski
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Desmons
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Jusal
authors.initials: J
authors.lastname: Quanico
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Fatou
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.|ONCOLille, Maison Régionale de la Recherche Clinique, Lille, France.
authors.forename: Jean-Pascal
authors.initials: JP
authors.lastname: Gimeno
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Franck
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Salzet
authors.affiliation: Univ. Lille, Inserm, U1192 - Protéomique Réponse Inflammatoire Spectrométrie de Masse - PRISM, Lille, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Fournier
mesh_terms: D000818:Animals; D001923:Brain Chemistry / Q000235:genetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D011506:Proteins / Q000235:genetics* / Q000302:isolation & purification; D040901:Proteomics / Q000379:methods*; D051381:Rats; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D011506:Proteins
keywords: LESA; Protein micro-extraction; Surface sampling; Technology; Tissue microproteomics