title: Characterization of the liver tissue interstitial fluid (TIF) proteome indicates potential for application in liver disease biomarker discovery.
abstract: Tissue interstitial fluid (TIF) forms the interface between circulating body fluids and intracellular fluid. Pathological alterations of liver cells could be reflected in TIF, making it a promising source of liver disease biomarkers. Mouse liver TIF was extracted, separated by SDS-PAGE, analyzed by linear ion trap mass spectrometer, and 1450 proteins were identified. These proteins may be secreted, shed from membrane vesicles, or represent cellular breakdown products. They show different profiling patterns, quantities, and possibly modification/cleavage of intracellular proteins. The high solubility and even distribution of liver TIF supports its suitability for proteome analysis. Comparison of mouse liver TIF data with liver tissue and plasma proteome data identified major proteins that might be released from liver to plasma and serve as blood biomarkers of liver origin. This result was partially supported by comparison of human liver TIF data with human liver and plasma proteome data. Paired TIFs from tumor and nontumor liver tissues of a hepatocellular carcinoma patient were analyzed and the profile of subtracted differential proteins supports the potential for biomarker discovery in TIF. This study is the first analysis of the liver TIF proteome and provides a foundation for further application of TIF in liver disease biomarker discovery.
authors.affiliation: State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing 102206, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
authors.forename: Songfeng
authors.initials: S
authors.lastname: Wu
authors.forename: Dong
authors.initials: D
authors.lastname: Yang
authors.forename: Yujuan
authors.initials: Y
authors.lastname: Yan
authors.forename: Kehui
authors.initials: K
authors.lastname: Liu
authors.forename: Jinglan
authors.initials: J
authors.lastname: Wang
authors.forename: Longqin
authors.initials: L
authors.lastname: Sun
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
authors.forename: Handong
authors.initials: H
authors.lastname: Wei
authors.forename: Yunping
authors.initials: Y
authors.lastname: Zhu
authors.forename: Baocai
authors.initials: B
authors.lastname: Xing
authors.forename: Xiaohang
authors.initials: X
authors.lastname: Zhao
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Qian
authors.forename: Ying
authors.initials: Y
authors.lastname: Jiang
authors.forename: Fuchu
authors.initials: F
authors.lastname: He
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D015153:Blotting, Western; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007526:Isoelectric Point; D008099:Liver / Q000378:metabolism*; D008107:Liver Diseases / Q000378:metabolism*; D051379:Mice; D020543:Proteome
chemical_list: D015415:Biomarkers; D020543:Proteome