FIGURE 7.

Effect of TIMP-3 mutants on aggrecan degradation in porcine cartilage explants. A–C, porcine articular cartilage explants were cultured in cartilage medium with 0.1% FCS (250 μl) and/or IL-1 (10 ng/ml) and/or wild-type TIMP-3 (A), K26A/K45A (B), or K42A/K110A (C) (0, 10, 50, or 100 nm). After 2 days, conditioned media were harvested, and aggrecan degradation was analyzed by immunoblotting with the anti-¹⁷⁷²AGEG neoepitope antibody (representative blot shown) and DMMB assay (graph showing μg of aggrecan released, mean ± S.D. (error bars), n = 3 biological replicates). *, p ≤ 0.05; **, p ≤ 0.01; ***, p ≤ 0.001 compared with IL-1-stimulated explants. The vertical line indicates where a single lane has been cropped from the images.