Morphological studies of hepatic tissue of mice reinfected with dengue virus serotypes 1 or 2

Submitted by Sandra Infurna ([email protected]) on 2018-04-26T10:48:54Z No. of bitstreams: 1 debora_vieira_etal_IOC_2011.pdf: 1565061 bytes, checksum: 0712963f06509eec67a0a67bacaa8696 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-04-26T10:59:30Z (GMT) No. of bitstreams: 1 debora_vieira_etal_IOC_2011.pdf: 1565061 bytes, checksum: 0712963f06509eec67a0a67bacaa8696 (MD5)Made available in DSpace on 2018-04-26T10:59:30Z (GMT). No. of bitstreams: 1 debora_vieira_etal_IOC_2011.pdf: 1565061 bytes, checksum: 0712963f06509eec67a0a67bacaa8696 (MD5) Previous issue date: 2010Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Universidade Federal do Rio de Janeiro. Instituto de Ciências Biológicas. Departamento de Histologia e Embriologia. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Flavivírus. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Flavivírus. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.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

Histopathological and ultrastructural studies of lung tissue of mice reinfected with dengue virus serotypes 1 or 2

Submitted by Sandra Infurna ([email protected]) on 2018-08-27T14:09:09Z No. of bitstreams: 1 enderson_silva_etal_IOC_2009.pdf: 405933 bytes, checksum: b6dbfa7e1119742c0d02559616ace815 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-08-27T14:17:42Z (GMT) No. of bitstreams: 1 enderson_silva_etal_IOC_2009.pdf: 405933 bytes, checksum: b6dbfa7e1119742c0d02559616ace815 (MD5)Made available in DSpace on 2018-08-27T14:17:42Z (GMT). No. of bitstreams: 1 enderson_silva_etal_IOC_2009.pdf: 405933 bytes, checksum: b6dbfa7e1119742c0d02559616ace815 (MD5) Previous issue date: 2009Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Universidade Federal do Rio de Janeiro. Instituto de Ciências Biomédicas. Departamento de Histologia e Embriologia,. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Flavivírus. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Flavivírus. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Morfologia e Morfogênese Viral. Rio de Janeiro, RJ. Brasil.Histological and ultrastructural alterations in lung of BALB/c mice reinfected with heterologous DENV by the intravenous route with non-neuroadapted dengue viruses serotypes 1 and 2 were analyzed. The lung samples were processed following the standard techniques of photonic and transmission electron microscopy. Morphological studies showed breakdown of alveolocapilar barrier leading to alveolitis, focal zones of collapse, and intraalveolar hemorrhage. Inside alveolar septa, congested capillaries exhibited neutrophils and platelets. Alveolar capillary endothelial cells exhibited aspects of activation with exuberant phylopodia and intracytoplasmic vesicles and vacuoles. Morphometrical analyses demonstrated an increase of the surface density of interalveolar septa in all reinfected mice while alveolar space density was decreased. All these morphometrical data corroborated the histological features emphasizing the alveolocapilar breakdrown in dengue infected animals. Important is the fact that reinfection leads to intraalveolar fibrogenesis as demonstrated by histomorphometry and ultrastructural studies. DENV particles, antigens and RNA were observed 72 hours post-reinfection in mosquito cells (C6/36) inoculated with sera of the animals. The morphological alterations observed in lungs were similar to the observed in human cases of dengue fever and dengue hemorrhagic fever. The present study demonstrates that the BALB/c mice, during the secondary infection by a heterologous serotype of DENV, develop morphological alterations in lung tissue more severe than those observed in the primary infection