Early and late pathogenic events of newborn mice encephalitis experimentally induced by itacaiunas and curionópolis bracorhabdoviruses infection.
In previous reports we proposed a new genus for Rhabdoviridae and described neurotropic preference and gross neuropathology in newborn albino Swiss mice after Curionopolis and Itacaiunas infections. In the present report a time-course study of experimental encephalitis induced by Itacaiunas and Curionopolis virus was conducted both in vivo and in vitro to investigate cellular targets and the sequence of neuroinvasion. We also investigate, after intranasal inoculation, clinical signs, histopathology and apoptosis in correlation with viral immunolabeling at different time points. Curionopolis and Itacaiunas viral antigens were first detected in the parenchyma of olfactory pathways at 2 and 3 days post-inoculation (dpi) and the first clinical signs were observed at 4 and 8 dpi, respectively. After Curionopolis infection, the mortality rate was 100% between 5 and 6 dpi, and 35% between 8 and 15 dpi after Itacaiunas infection. We identified CNS mice cell types both in vivo and in vitro and the temporal sequence of neuroanatomical olfactory areas infected by Itacaiunas and Curionopolis virus. Distinct virulences were reflected in the neuropathological changes including TUNEL immunolabeling and cytopathic effects, more intense and precocious after intracerebral or in vitro inoculations of Curionopolis than after Itacaiunas virus. In vitro studies revealed neuronal but not astrocyte or microglial cytopathic effects at 2 dpi, with monolayer destruction occurring at 5 and 7 dpi with Curionopolis and Itacaiunas virus, respectively. Ultrastructural changes included virus budding associated with interstitial and perivascular edema, endothelial hypertrophy, a reduced and/or collapsed small vessel luminal area, thickening of the capillary basement membrane, and presence of phagocytosed apoptotic bodies. Glial cells with viral budding similar to oligodendrocytes were infected with Itacaiunas virus but not with Curionopolis virus. Thus, Curionopolis and Itacaiunas viruses share many pathological and clinical features present in other rhabdoviruses but distinct virulence and glial targets in newborn albino Swiss mice brain.
Diniz
José Antonio Picanço
JA
Instituto Evandro Chagas, Belém, Brazil.
Dos Santos
Zaire Alves
ZA
Braga
Marcio Augusto Galvão
MA
Dias
Adila Liliane Barros
AL
da Silva
Daisy Elaine Andrade
DE
de Almeida Medeiros
Daniele Barbosa
DB
de Souza Barros
Vera Lucia Reis
VL
Chiang
Jannifer Oliveira
JO
de Freitas Zoghbi
Kendra Eyllen
KE
Quaresma
Juarez Antônio Simões
JA
Takiya
Christina Maeda
CM
Moura Neto
Vivaldo
V
de Souza
Wanderley
W
da Costa Vasconcelos
Pedro Fernando
PF
Diniz
Cristovam Wanderley Picanço
CW
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis; D001921:Brain / Q000196:embryology / Q000473:pathology / Q000821:virology; D002478:Cells, Cultured; D004195:Disease Models, Animal; D018792:Encephalitis, Viral / Q000209:etiology / Q000473:pathology*; D005260:Female; D005455:Fluorescent Antibody Technique; D007124:Immunoenzyme Techniques; D051379:Mice; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism / Q000821:virology; D009474:Neurons / Q000166:cytology / Q000378:metabolism / Q000821:virology; D011247:Pregnancy; D012209:Rhabdoviridae / Q000145:classification* / Q000472:pathogenicity*; D018353:Rhabdoviridae Infections / Q000473:pathology* / Q000821:virology