Figure 4: Changes in various cellular functions in primary human liver stellate cells treated with ZnO nanoparticles or dissolved ZnSO4, at 30 μg/mL. Cells were treated in triplicate or quadruplicate with ZnO nanoparticles, or ZnSO4, for each treatment time-point (6 and 24 h). Signal levels representing different cell functions were averaged, and are expressed here as the percentage of untreated cells set as 100%. Data used to generate this figure, and associated standard errors of means and statistical significance, are supplied separately in Supplementary Table 2.