Collagen II synthesis in the scaffold group (A,B,C) and control group (D,E,F) was analyzed by immunofluorescence staining, including nuclear counterstaining with DAPI (A,D), anti-collagen II staining in red (B,E); merged images are also shown (C,F). (G) qRT-PCR analysis of gene expression and (H) western blotting for collagen II, aggrecan, sox9 and collagen I, using GAPDH as the internal reference. The nanofibrous scaffolds generally enhanced cartilage-specific gene expression and protein levels. ♦ Statistically significant difference compared with the control group (p<0.05); • Statistically significant difference compared with the control group (p<0.01).