Fig. 4. The effect of sphingolipid and linoleic acid metabolism pathways on S. aureus infected macrophages. (A and B) The relative ratios of internalized bacteria (A) or intracellular survival of S. aureus (B) determined for myriocin and fumonisin B1. For internalized bacteria assay, cells were treated with myriocin and fumonisin B1 for 24 hours before and during the infection. For intracellular survival, S. aureus (USA 300 strain) was determined after myriocin and fumonisin B1 treatments for 24 hours. (C) The relative ratios of intracellular survival of S. aureus (USA 300 strain) determined after treatment with four fatty acids for 24 hours. (D) The relative ratios of intracellular survival of S. aureus (ATCC29213 strain) determined after linoleic acid treatment for 24 hours. (E) The relative ratios of intracellular survival of Staphylococcus epidermidis (ATCC12228 strain) and Escherichia coli (CFT073 strain) determined after linoleic acid treatment for 24 hours. Data are given as mean ± SD of three independent experiments. One-way ANOVA when compared with the DMSO control group. *p < 0.05, **p < 0.01 and ***p < 0.001.