Binding of FITC-labeled LPS to endothelial cells. HUVECs were incubated with FITC-LPS (175 ng/mL) for 10, 15, 30, 60, 120, and 180 minutes in the absence (left column) and in the presence (right column) of C1INH (150 μg/mL) and then were examined using laser scanning confocal microscopy.