Figure 2.

Effects of NF-kB ablation on ROS production in U937 cells. DCFH-DA preloaded U937-DN-IkB (NFkB DN) were exposed to HSV-1 (MOI = 50 PFU/cell) or vehicle alone (mock) from 0.5 to 2 h for ROS detection by fluorescence microscopy. In each experiment, DCFH-DA preloaded wt U937 cells (NFkB wt), exposed or mock exposed to HSV-1 for 0.5 h, were also included as positive controls. (A) Representative images by 20× objective. Times of HSV-1 exposure (h) are reported in the FITC frames (0 = mock infected U937-DN-IkB). Scale bar = 50 μm. (B) % of DCF fluorescence positive cells (mean + S.D) from 8 frames randomly selected from two independent experiments (4 frames each). * p < 0.01, ** p < 0.001 vs. control (h = 0). (C) DCFH-DA preloaded NFkB DN or wt U937 cells, were treated with 5 µM H₂O₂ for a further 30 min and then washed and analysed for ROS production by fluorescence microscopy. Objective 40×, scale bar = 50 μm.