Figure 1.

Effects of BMSC-EVs on IDD mice. (a) The morphology of EVs observed under the TEM. (b) The particle size distribution of EVs analyzed by NTA. (c) The protein levels of EV markers CD63, TSG101, and CD81 and negative control calnexin detected by Western blot analysis. (d) The NP and cartilage AF of IVD after modeling detected by safranin O staining (n = 10). The first row shows the staining image of IVD as a whole, the second row displays the detailed view of NP tissues, and the third row presents the detailed view of boundary between NP and AF tissues. ^∗p < 0.05vs. IDD mice at the 6^th month (M). (e) The histopathology of NP and the AF of NP and cartilage detected by safranin O staining (n = 10). The first row shows the staining image of IVD as a whole, the second row displays the detailed view of NP tissues, and the third row presents the detailed view of boundary between NP and AF tissues. ^∗p < 0.05vs. IDD mice and ^#p < 0.05vs. IDD mice at the 6^th week (W). (f) The levels of Col II and MMP13 in NP tissues measured by immunofluorescence staining (n = 10). Cell experiments were repeated for three times independently.