Starved BMSCs-Evs enhanced the matrix synthesis of chondrocytes. Cartilage-related gene expression of aggrecan, Col2 and Col 10 was measured by qPCR, and the statistical results are presented. C-D. Cartilage-related protein expression tested by western blot and the statistical results. E. Alcian blue- and collagen-related staining of rBMSC microspheres. *P < 0.05, **P < 0.01, ****P < 0.0001. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)