Fig. 5.

The effects of incorporating negatively charged chondroitin sulfate into PEG hydrogels and applying dynamic mechanical stimulation on nitric oxide production as measured by nitrite production (A,B) and cell proliferation (C,D) for chondrocytes encapsulated in PEG-only or PEG-ChS gels and cultured as uncompressed controls (black bars) or dynamically strained specimen (gray bars). To isolate the effects of dynamic loading, mean responses for the dynamically strained specimen were normalized to their respective uncompressed control counterparts and presented as a percent change from uncompressed control (B,D). Data are given by mean ± standard deviation (n =4–5); *p < 0.05, **p<0.01, ***p<0.001; # p<0.05, ##p<0.01, ###p<0.001. An asterisk(s) above a column in B and D panels denotes significance from uncompressed control.