Fig. 5

Modulatory effects of surface functional groups on CuO bioreactivity. As shown in (a), at each dose, the experimental group of every functionalized material was compared against core CuO in PBS- or OVA-challenged mice. The most drastic effect was induced by PEGylation, as seen from the Number of DEGs and enriched biological processes (a). The top canonical pathways enriched by down-regulated genes in PBS mice exposed to 2.5 μg of CuO PEG as compared with core CuO at the same dose, or enriched by up-regulated genes in OVA-challenged mice exposed to 40 μg of CuO PEG as compared with core CuO at the same dose are shown in (b) and (c) respectively. b-c The x-axis represents the pathways identified. The y-axis on left shows the -log(P value) calculated based on Fisher’s exact test. Threshold level is set on a P value of 0.05. The y-axis on right represents a ratio between a number of DEGs in a given pathway with a cut-off -log(P value) > 2, divided by total number of genes belonging to the reference gene set of the pathway. The orange- and blue-colored bars indicate predicted pathway activation or inhibition, respectively