Innate Immune Control of West Nile Virus Infection

Section of Infectious Diseases, Yale School of Medicine, New Haven, CT, USA.
Cellular Microbiology (Impact Factor: 4.92). 07/2011; 13(11):1648-58. DOI: 10.1111/j.1462-5822.2011.01649.x
Source: PubMed


West Nile virus (WNV), from the Flaviviridae family, is a re-emerging zoonotic pathogen of medical importance. In humans, WNV infection may cause life-threatening meningoencephalitis or long-term neurologic sequelae. WNV is transmitted by Culex spp. mosquitoes and both the arthropod vector and the mammalian host are equipped with antiviral innate immune mechanisms sharing a common phylogeny. As far as the current evidence is able to demonstrate, mosquitoes primarily rely on RNA interference, Toll, Imd and JAK-STAT signalling pathways for limiting viral infection, while mammals are provided with these and other more complex antiviral mechanisms involving antiviral effectors, inflammatory mediators, and cellular responses triggered by highly specialized pathogen detection mechanisms that often resemble their invertebrate ancestry. This mini-review summarizes our current understanding of how the innate immune systems of the vector and the mammalian host react to WNV infection and shape its pathogenesis.

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Available from: Penghua Wang
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    • "Evidence is also emerging that CLRs recognizing glycosylated flaviviruses may play a role in the infection of vector mosquito species (Arjona et al., 2011; Cheng et al., 2010). "
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    • "In the context of vector-borne infections, this finding is of particular importance. We already know that to program innate immune response, a mixture of primary responder cells such as macrophages, neutrophils and dendritic cells infiltrate at the site of infection and work together to clear the pathogen which has been transferred through a mosquito bite [31], [32], [33]. One might hypothesize that in these circumstances; SGE-induced apoptosis obstructs primary cells, suppresses effecter mechanisms, and eventually interferes in pathogen clearance. "
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    Full-text · Article · Jul 2012 · PLoS ONE
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    • "Although a considerable amount of information is available about humoral defence reactions in bees directed against bacterial and fungal infections, antiviral mechanisms in this social insect are not known at all. Studies in the fruit fly Drosophila and in mosquitos (Aedes aegypti and Anopheles gambiae) have provided convincing evidence that an intrinsic cell defence mechanism based on RNA interference plays a major role in antiviral immune responses against single-stranded and double-stranded RNA viruses [3, 23, 29, 44, 51, 53, 54, 57], whereas reports about the significance of inducible antiviral reactions are somehow contradictory. Sabatier et al. [43] did not detect any of the known AMPs in the haemolymph of Drosophila flies challenged with drosophila C virus (DCV) (a member of the family Dicistroviridae). "
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