%0 Journal Article
%T Suppression of MMP activity in bovine cartilage explants cultures has little if any effect on the release of aggrecanase-derived aggrecan fragments
%A Bijue Wang
%A Pingping Chen
%A Anne-Christine Jensen
%A Morten A Karsdal
%A Suzi H Madsen
%A Bodil-Cecilie Sondergaard
%A Qinlong Zheng
%A Per Qvist
%J BMC Research Notes
%D 2009
%I BioMed Central
%R 10.1186/1756-0500-2-259
%X Bovine cartilage explants were cultured in the presence or absence of the catabolic cytokines oncostatin M (OSM) and tumor necrosis factor alpha (TNF¦Á). In parallel, explants were co-cultured with protease inhibitors such as GM6001, TIMP1, TIMP2 and TIMP3. Fragments released into the supernatant were determined using a range of neo-epitope specific immunoassays; (1) sandwich 342FFGVG-G2 ELISA, (2) competition NITEGE373ELISA (3) sandwich G1-NITEGE373 ELISA (4) competition 374ARGSV ELISA, and (5) sandwich 374ARGSV-G2 ELISA all detecting aggrecan fragments, and (6) sandwich CTX-II ELISA, detecting C-telopeptides of type II collagen. We found that (1) aggrecanase-derived aggrecan fragments are released in the early (day 2-7) and mid phase (day 9-14) into the supernatant from bovine explants cultures stimulated with catabolic cytokines, (2) the release of NITEGE373 neo-epitopes are delayed compared to the corresponding 374ARGSV fragments, (3) the MMP inhibitor GM6001 did not reduce the release of aggrecanase-derived fragment, but induced a further delay in the release of these fragments, and finally (4) the MMP-derived aggrecan and type II collagen fragments were released in the late phase (day 16-21) only.Our data support the model, that aggrecanases and MMPs act independently in the processing of the aggrecan molecules, and furthermore that suppression of MMP-activity had little if any effect on the quantity of aggrecanase-derived fragments released from explants cultures.All though the pathogenesis joint diseases is not fully understood, major efforts have been allocated to the development of drugs aimed at down regulating proteases expression and acitivity involved in the degradation of the extracellular matrix of the joint. The protease repertoire of the chondrocytes is wide, and both aggrecanases, MMPs, and cathepsins have been associated with degradation and/or repair of the ECM of the articular cartilage in the joint [1-7].To study the metabolic events leading to
%U http://www.biomedcentral.com/1756-0500/2/259