Figure 4. For both experiments, U937 cells were perfused over the retinal vascular endothelial cell (REC) monolayer culture in 25 mM glucose medium, which were transfected with scrambled siRNA or ICAM-1 siRNA for 24 h, followed by treatment with and without TNF-α for 4 h. Images were taken at the second hour after flow was initiated; data are expressed as the mean number of adhering cells/field ± SD for at least four different fields of view. A: ICAM-1 siRNA inhibited TNF-α induced monocytes adhesion to RECs in a flow chamber system. *p<0.05 versus Sc siRNA. ^#p<0.05 versus Sc siRNA + TNF-α. ^$p<0.05 versus ICAM-1siRNA. B: ELISA results of ICAM-1 concentration after ICAM-1 siRNA transfection following exposure to the flow chamber. *p<0.05 versus Sc siRNA. ^#p<0.05 versus Sc siRNA + TNF-α. n=3, data are mean±SEM.