Fig. 6

(A) Apoptosis in the knee joint cartilage was detected 6 and 12 weeks after chemical induction of OA by TUNEL staining in the articular cartilage regions. Apoptotic cells were stained with green positive fluorescence. The ratio of TUNEL-positive nuclei to total nuclei was quantified for each group (expressed as %, n = 8 in each group). Scale bars: 25 μm (*, p < 0.05). (B) MMP-9 and type II collagen were detected by immunofluorescence staining. (DAPI: blue, MMP-9: green, type II collagen: red) Scale bars: 100 μm. (C) Mesenchymal stem cell (MSC) recruitment by SAP-SP conjugates was investigated. SAP-SP conjugates are effective for the recruitment of MSCs into the arthritic defect region. The representative images of articular cartilage defect sites from each group after CD29 and CD90 staining. Scale bars: 100 μm