Autor(es)Glaser Robert L, Meola Mark A

ResumoThe bacterial endosymbiont Wolbachia pipientis has been shown to increase host resistance to viral infection in native Drosophila hosts - in the normally Wolbachia-free heterologous host Aedes aegypti when infected by Wolbachia from Drosophila melanogaster or Aedes albopictus. Wolbachia infection has not yet been demonstrated to increase viral resistance in a native Wolbachia-mosquito host system. In this study, we investigated Wolbachia-induced resistance to West Nile virus (WNV; Flaviviridae) by measuring infection susceptibility in Wolbachia-infected - Wolbachia-free D. melanogaster - Culex quinquefasciatus, a natural mosquito vector of WNV. Wolbachia infection of D. melanogaster induces strong resistance to WNV infection. Wolbachia-infected flies had a 500-fold higher ID50 for WNV - produced 100,000-fold lower virus titers compared to flies lacking Wolbachia. The resistance phenotype was transmitted as a maternal, cytoplasmic factor - was fully reverted in flies cured of Wolbachia. Wolbachia infection had much less effect on the susceptibility of D. melanogaster to Chikungunya (Togaviridae) - La Crosse (Bunyaviridae) viruses. Wolbachia also induces resistance to WNV infection in Cx. quinquefasciatus. While Wolbachia had no effect on the overall rate of peroral infection by WNV, Wolbachia-infected mosquitoes produced lower virus titers - had 2 to 3-fold lower rates of virus transmission compared to mosquitoes lacking Wolbachia. This is the first demonstration that Wolbachia can increase resistance to arbovirus infection resulting in decreased virus transmission in a native Wolbachia-mosquito system. The results suggest that Wolbachia reduces vector competence in Cx. quinquefasciatus, - potentially in other Wolbachia-infected mosquito vectors.

ImprentaPloS One, v. 5, n. 8, p. e11977, 2010

DescritoresChikungunya virus - Arbovirus ; Chikungunya virus - Flaviviridae ; Chikungunya virus - Pathogenesis ; Chikungunya virus - Viral infections ; Chikungunya Virus - Virus ; Chikungunya virus - Transmission ; Chikungunya virus - Chikungunya fever ; Chikungunya virus - Immunology ; Chikungunya virus - Public health

Data de Publicação:2010