Gene expression of hMSCs cultured on silk scaffolds, SHG ceramic scaffolds, SHG-silk scaffolds and biphasic scaffolds in chondrogenic medium over 21 days, expressed as fold increase from undifferentiated cells at day 0. (A, B) Sox-9, (C, D) collagen type II, (E, F) aggrecan, and (G, H) collagen type X. (A, C, E, G) show differences in expression levels between groups (*p < 0.05 between groups) while (B, D, F, H) show changes in expression levels within each group over the culture period (#p < 0.05 within the same group compared to previous time point).