FIG 6.
A549 spike-transfected culture medium induces ROS generation in endothelial cells. ROS production in two endothelial cells (A and B) exposed to A549 spike CM was measured in the presence or absence of inhibitors. CM decreased the proliferative ability of the endothelial cells, as displayed by progressively reduced MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide] activity compared to that of control CM. Experiments were performed in triplicate. ROS levels were increased approximately 2-fold in experimental cells compared to those in mock-treated control cells. Experiments were performed in triplicate. The percentage of adhesion was determined by a release of fluorescence from human monocytes (THP-1) after 6 h of adhesion on treated TMNK-1 (C) and EAhy926 (D) cells. Experiments were performed in duplicate. The results are presented as mean ± standard deviation. *, P < 0.05.