Figure 4. BMSC exosomes inhibited chondrocyte hypertrophy and reduced osteophyte formation in the rat model. (A) and (B) Immunohistochemistry and analysis of collagen II in knee sections. Scale bar: 50 μm. (C) and (D) Immunohistochemistry and analysis of collagen X in knee sections. Scale bar: 50 μm. (E) Micro-CT scan and three-dimensional reconstruction of the knee joint in each experimental group. (F) Osteophyte score and quantitative analysis of the volume of the region of interest (ROI). (G–K) Western blot results and analyses of cartilage tissue. *p < 0.05 compared to the Sham group; # p < 0.05 compared to the PBS group.