Figure 3. Wnt-1 inhibits mineral formation by DPSCs. (A) Wnt-1 inhibits ALP activity in DPSCs after 5 days of culture in differentiating medium. The experiments were performed twice, and the results represent average values from triplicate assays. (B) Secreted Wnt-1 inhibited ALP activity. Mixed cultures were established with various ratios of DPSC/V to DPSC/Wnt-1 cells as indicated and grown in differentiating medium for 12 days. Results were quantified by densitometry to compare staining intensities. Sample staining was repeated in duplicate. DPSC/V results were set to 100% staining and DPSC/Wnt-1 results to 0% staining for standardization of the mixed cultures. (C) Wnt-1 inhibited mineral formation of DPSCs after 14 days of culture in differentiation medium. Both DPSC/V and DPSC/Wnt-1 cells were induced to differentiate with dexamethasone and β-GP. Two wks after induction, cells were stained with Alizarin red. The experiments were performed twice, and the results represent average values from triplicate assays. ALP, alkaline phosphatase; β-GP, β-glycerophosphate.