Cytokine expression by ADSCs, grown on the piezoelectric PLLA nanofiber scaffold under applied US in vitro .

a. A schematic representation of our setup for seeding ADCSs onto the negative side of the PLLA scaffolds and treating them with US. The US generates a controllable pressure, inducing the formation of electrical charges on the surface of the nanofiber films, which facilitate osteogenesis of the cultured cells. b. A quantitative comparison of BMP-2 produced by the cells in different treatment groups. c. A quantitative comparison of TGF-β produced by the cells in different treatment groups. All data were normalized with relative cell population quantified in protein assays (n = 3). One-way ANOVA followed by Tukey’s post hoc test was used to calculate statistical significance. In the figure, * represents a significance level of 0.05, and *** represents a significance level of 0.001.