Recent Advances in Japanese Encephalitis

Solomon, Tom

doi:10.1080/713831485

Cited by 7 publications

(7 citation statements)

References 10 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Flaviviral NS5 is known to possess guanylyltransferase activity that helps in the synthesis of methylated cap structure at the 59 end of the viral genome that plays a crucial role in the translation and stability of mRNAs [34]. The JEV E glycoprotein is believed to be involved in viral adhesion and entry into host cells, hemagglutination, cellular tropism, viral virulence, and the induction of protective immune responses [35]. Decreased expression of these proteins indicates that viral replication and production of new infective viral particles are inhibited due to the MOs.…”

Section: Discussionmentioning

confidence: 99%

Antiviral and Neuroprotective Role of Octaguanidinium Dendrimer-Conjugated Morpholino Oligomers in Japanese Encephalitis

2010

View full text Add to dashboard Cite

BackgroundJapanese encephalitis (JE), caused by a mosquito-borne flavivirus, is endemic to the entire south-east Asian and adjoining regions. Currently no therapeutic interventions are available for JE, thereby making it one of the most dreaded encephalitides in the world. An effective way to counter the virus would be to inhibit viral replication by using anti-sense molecules directed against the viral genome. Octaguanidinium dendrimer-conjugated Morpholino (or Vivo-Morpholino) are uncharged anti-sense oligomers that can enter cells of living organisms by endocytosis and subsequently escape from endosomes into the cytosol/nuclear compartment of cells. We hypothesize that Vivo-Morpholinos generated against specific regions of 3′ or 5′ untranslated regions of JEV genome, when administered in an experimental model of JE, will have significant antiviral and neuroprotective effect.Methodology/Principal FindingsMice were infected with JEV (GP78 strain) followed by intraperitoneal administration of Morpholinos (5 mg/kg body weight) daily for up to five treatments. Survivability of the animals was monitored for 15 days (or until death) following which they were sacrificed and their brains were processed either for immunohistochemical staining or protein extraction. Plaque assay and immunoblot analysis performed from brain homogenates showed reduced viral load and viral protein expression, resulting in greater survival of infected animals. Neuroprotective effect was observed by thionin staining of brain sections. Cytokine bead array showed reduction in the levels of proinflammatory cytokines in brain following Morpholino treatment, which were elevated after infection. This corresponded to reduced microglial activation in brain. Oxidative stress was reduced and certain stress-related signaling molecules were found to be positively modulated following Morpholino treatment. In vitro studies also showed that there was decrease in infective viral particle production following Morpholino treatment.Conclusions/SignificanceAdministration of Vivo-Morpholino effectively resulted in increased survival of animals and neuroprotection in a murine model of JE. Hence, these oligomers represent a potential antiviral agent that merits further evaluation.

show abstract

Section: Discussionmentioning

confidence: 99%

Antiviral and Neuroprotective Role of Octaguanidinium Dendrimer-Conjugated Morpholino Oligomers in Japanese Encephalitis

2010

View full text Add to dashboard Cite

show abstract

“…Japanese encephalitis virus (JEV), one of the causes for epidemic encephalitis, belongs to the family of Flaviviridae. It is widely distributed in Asia (Harris et al, 2006;Solomon, 2003;Tsai, 2000). The outbreaks of emerging flaviviruses have made the prevention and treatment of flavivirus infection a global public health concern (Hanna et al, 1996;Mackenzie et al, 2004;Wang et al, 2007).…”

Section: Introductionmentioning

confidence: 99%

The DEAD-box RNA helicase DDX5 acts as a positive regulator of Japanese encephalitis virus replication by binding to viral 3′ UTR

et al. 2013

Antiviral Research

View full text Add to dashboard Cite

Japanese encephalitis virus (JEV), one of the causes for epidemic encephalitis, belongs to the family of Flaviviridae. In this study, we demonstrated that cellular DEAD-box RNA helicase DDX5 plays an important role in JEV replication. The knockdown of DDX5 was able to decrease JEV replication, and overexpression of DDX5 mutants lacking the helicase activity also reduced JEV replication, suggesting the helicase activity is essential for JEV replication. DDX5 knockdown did not affect virus assembly and release. GST-pulldown and co-immunoprecipitation experiments demonstrated that DDX5 could interact with JEV core protein, non-structural protein 3 (NS3) and 5 (NS5-MTase and NS5-RdRp domains). Meanwhile, we also confirmed that DDX5 interacts with these viral proteins during JEV infection. Confocal microscopy analysis showed that endogenous DDX5 is recruited to the cytoplasm and colocalizes with these viral proteins and viral RNA. RNA-pulldown experiment showed that DDX5 only binds to the JEV 3' untranslated region (UTR). Finally, we confirmed the role of DDX5 in JEV RNA replication using JEV-replicon system. In conclusion, we identified DDX5 as a positive regulator for JEV replication.

show abstract

“…tritaeniorhynchus is known to carry Japanese encephalitis (Airi & Kaur 2015) and in South Korea, they emerge in early May, peaking in mid-August, and continuing to emerge until late October. The main sources of infection of Japanese encephalitis are birds and hogs and infection is transmitted among these groups (Solomon 2003), however hogs are an amplifier host (Mullen & Durden 2002). In city centers without hoggeries, Japanese encephalitis infection rates are very low and in this study, the highest number of mosquitoes infected with this virus was collected from the rural cowshed, while the lowest incidence was recorded in mosquitoes collected from the urban sites and migratory bird habitat.…”

Section: Discussionmentioning

confidence: 99%

Species composition, seasonal prevalence and flavivirus occurrence of mosquitoes in Daegu and Gunwi, South Korea during the period of 2015–2016

Kim

Choi

Lee

et al. 2018

Entomological Research

View full text Add to dashboard Cite

As the vector‐borne diseases rapidly increased due to climate change, we investigated the incidence of flavivirus occurrence among female mosquito species in urban and rural study sites in Daegu and Gunwi, South Korea using Realtime PCR. We collected more individuals and more species of mosquito in 2016 than in 2015. In 2015, we recorded a total of 22,033 mosquitoes (Trap Index, 224.8) representing 10 species from 5 genera, whereas in 2016, a total of 27,137 mosquitoes (Trap Index, 278.7) representing 13 species from 6 genera were collected. The number of mosquitoes in 2016 was higher in all study sites, except in the migratory bird habitats where the number decreased. Of the 14 species collected over the two years, Aedes vexans nipponii and Anopheles spp. were dominant in the cowsheds in rural farmland; Culex pipiens complex, in urban residential areas; and, Anopheles spp. and Cu. pipiens complex in migratory bird habitats caught in a black light trap. Cu. pipiens complex and Ae. albopictus in urban parks and Ae. albopictus and Armigeres subalbatus in migratory bird habitats were the dominant species caught in BG‐sentinel traps. We found that the number of mosquitoes was highest during July–September. We analyzed 1,725 pools to detect flavivirus, where Chaoyang virus was detected among Ae. vexans niponii collected from cowsheds in rural farmland in 2016. The increased number of mosquitoes recorded in 2016 was mainly due to increased temperatures in the study areas, and reflected the change in study sites.

show abstract

Recent Advances in Japanese Encephalitis

Cited by 7 publications

References 10 publications

Antiviral and Neuroprotective Role of Octaguanidinium Dendrimer-Conjugated Morpholino Oligomers in Japanese Encephalitis

Antiviral and Neuroprotective Role of Octaguanidinium Dendrimer-Conjugated Morpholino Oligomers in Japanese Encephalitis

The DEAD-box RNA helicase DDX5 acts as a positive regulator of Japanese encephalitis virus replication by binding to viral 3′ UTR

Species composition, seasonal prevalence and flavivirus occurrence of mosquitoes in Daegu and Gunwi, South Korea during the period of 2015–2016

Contact Info

Product

Resources

About