Figure 5

Contribution of SOX11 to articular cartilage homeostasis in mice and humans. (A) Histological findings of articular cartilage after creating an experimental osteoarthritis model that induces instability in the knee joints of 8-week-old mice. HE and Safranin-O stainings, as well as immunohistochemical staining with an antibody to SOX11 (α-SOX11) or GDF5 (α-GDF5) were performed 4 weeks after surgery. A sham operation was performed using the same approach. Operations were performed in the medial side of knee joints. Dotted line highlights the region where Safranin-O staining is lost in the arthritic model. Red arrowheads indicate positive signal for SOX11 or GDF5. Scale bars, 500 μm. (B) H&E staining, Safranin-O staining and immunostaining with an antibody to human SOX11 in human knee cartilages, obtained as surgical specimens of total knee arthroplasty. Cartilage degradation was evaluated by the modified Mankin scoring system. The blue and red side bars indicate the articular cartilage layer and subchondral bone layer, respectively. Scale bars, 500μm.