title: An inflammatory equine model demonstrates dynamic changes of immune response and cartilage matrix molecule degradation in vitro.
abstract: The molecular aspects of inflammation were investigated in equine articular cartilage explants using quantitative proteomics. Articular cartilage explants were stimulated with interleukin (IL)-1β in vitro for 25 days, and proteins released into cell culture media were chemically labeled with isobaric mass tags and analyzed by liquid chromatography-tandem mass spectrometry. A total of 127 proteins were identified and quantified in media from explants. IL-1β-stimulation resulted in an abundance of proteins related to inflammation, including matrix metalloproteinases, acute phase proteins, complement components and IL-6. Extracellular matrix (ECM) molecules were released at different time points, and fragmentation of aggrecan and cartilage oligomeric matrix protein was observed at days 3 and 6, similar to early-stage OA in vivo. Degradation products of the collagenous network were observed at days 18 and 22, similar to late-stage OA. This model displays a longitudinal quantification of released molecules from the ECM of articular cartilage. Identification of dynamic changes of extracellular matrix molecules in the secretome of equine explants stimulated with IL-1β over time may be useful for identifying components released at different time points during the spontaneous OA process.
authors: Section of Pathology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences , Uppsala , Sweden .
authors: Emilia
authors: E
authors: Svala
authors: Maria
authors: M
authors: Löfgren
authors: Carina
authors: C
authors: Sihlbom
authors: Ulla
authors: U
authors: Rüetschi
authors: Anders
authors: A
authors: Lindahl
authors: Stina
authors: S
authors: Ekman
authors: Eva
authors: E
authors: Skiöldebrand
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism* / Q000473:pathology; D006736:Horses; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D053583:Interleukin-1beta / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism*; D010003:Osteoarthritis / Q000378:metabolism* / Q000473:pathology
chemical_list: D053583:Interleukin-1beta; D015850:Interleukin-6
keywords: Horse; IL-1β; matrix molecules; osteoarthritis; proteomics