a, Schematic of the experimental outline. Destabilization of the medial meniscus (DMM) was performed on adult mice, and the distal femurs were harvested after 8 weeks. Analysis was performed by IF, pentachrome, and Safranin-O Fast Green staining. b, Left, representative IF of indicated markers in sham and DMM joints. Scale bars 100μm. Right, Safranin-O Fast Green and pentachrome stains of sham and joints 8 weeks after DMM. Scale bars 500μm. (n = 3 per group). c, Quantification of IF stains in sham versus DMM. Graphs show mean + /- s.e.m. Two-tailed Student’s t-test. Exact P values to 2 significant figures. (n = 3 per group).