ABSTRACT
Objective To study the changes of tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), and soluble thrombomodulin (sTM) induced by dengue 2 virus (D 2V) infection of vascular endothelial cells. Methods The effects of D 2V infection on the production of t-PA, PAI-1, and sTM of human umbilical cord vein cells were studied. Results D 2V infection significantly induced the secretion of sTM and t-PA but showed no such effects on PAI-1 of human endothelial cells. Antibody against IL-6 inhibited D 2V-induced t-PA production of endothelial cells. A close correlation between serum levels of IL-6 and t-PA was found in dengue hemorrhagic fever (DHF) but not in dengue fever (DF) patients. Conclusion IL-6 can regulate D 2V-induced t-PA production of endothelial cells, suggesting that endothelial cells can be the target for D 2V infection and that D 2V-induced t-PA, TM, and IL-6 production of endothelial cells may contribute to the pathogenic development of dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS).