MORPHOLOGICAL STUDIES OF HEPATIC TISSUE OF MICE REINFECTED WITH DENGUE VIRUS SEROTYPES 1 OR 2

Histopathological and ultrastructural aspects of liver of non-neuroadapted BALB/c mice reinfected by the intravenous route with dengue virus serotypes 1 and 2 were presented. The hepatic tissue was processed following the standard techniques for photonic and transmission electron microscopy. Morphological studies showed vacuolization of hepatocytes, inflammatory cells inside sinusoidal capillaries, enlargement of sinusoidal capillaries, foci of hemorrhage inside the interstitium, increase of surface density of reticular fibres, increase of numerical density of sinusoidal cells, decrease of surface density of hepatocytes, edema in the peri centrolobular vein space and presence of phyllopods and pseudopod-like extensions in endothelial cells. DENV particles, virus antigens and DENV RNA were observed in mosquito cells (C6/36) inoculated with sera of the animals 72 hours post-reinfection. The hepatic alterations observed in our experimental model were similar to those observed in human cases of dengue hemorrhagic fever. The present study shows that BALB/c mice reinfected with a heterologous serotype of DENV develop more severe lesions than those observed in mice in primary infection. DOI:  http://dx.doi.org/10.17525/vrr.v15i2.68