Fig. 3

Intra- and extravascular cells in the pathogenesis of dengue. DENV (DV) infection of monocytes triggers the intravascular release of numerous immunological factors to modulate the function of vascular endothelial cells. Besides TNF, other monocyte-secreted factors can prime or trigger endothelial cell permeability leading to vascular leakage and leukocyte transmigration to extravascular tissues. Extravascular mast cells and macrophages are target cells for DENV infection which elicits production of cytokines, chemokines, lipid-derived mediators and proteases which also contribute to endothelial cell permeability. In addition, macrophage production of TNF enhances DENV-infected endothelial cell death which leads to hemorrhage development