To understand human response to avian H9N2 influenza, we investigated the effects of the viral infection on A549, HepG2, and HeLa cells at low and high MOIs. To identify virus-host interplay, expression of Mx and NP genes was measured in the cells supernatants. Cell viability and apoptosis were evaluated by MTT assay, DNA fragmentation, and florescent staining. The virus titration and NP gene t...

Sambucus nigra (elder) are broadly used species to treat microbial infections. Thepotential antiviral activity and mechanism action of elder fruit (EF) in human epithelium cell(A549) cultures infected with H9N2 influenza virus were determined. The effect of variousconcentrations of EF on influenza virus replication was examined by using virus titration,quantitative real time RT-PCR, fusion and ...

Human infection with an avian influenza virus persists. To prepare for a potential outbreak of avian influenza, we constructed a candidate vaccine virus (CVV) containing hemagglutinin (HA) and neuraminidase (NA) genes of a H5N1 virus and evaluated its antigenic stability after serial passaging in embryonated chicken eggs. The passaged CVV harbored the four amino acid mutations (R136K in PB2; E3...

H9N2 influenza A viruses are currently widespread in chickens, quail, and other poultry in Asia and have caused a few cases of influenza in humans. In this study, we found that H9N2 viruses from Hong Kong live bird markets have receptor specificity similar to that of human H3N2 viruses. In addition, the neuraminidase of poultry H9N2 viruses has mutations in its hemadsorbing site, a characterist...

BACKGROUND Flock surveillance systems for avian influenza (AI) virus play a critical role in countries where vaccination is not practiced so as to establish the epidemiological characteristics of AI needed for the development of prevention and control strategies in such countries. MATERIALS AND METHODS As part of routine AI monitoring in southwest Nigeria, a competitive ELISA was used for det...

We report the complete genome sequence of a natural recombinant H9N2 avian influenza virus (AIV) that was isolated from a wild bird in the Republic of Korea in 2005. The genomic sequence and phylogenetic analyses showed that this virus contains six genes of North American lineage AIV and two genes of Eurasian lineage AIV. These data are beneficial for investigating the ecology and epidemiology ...

The genome sequence of the strain A/chicken/Changzhou/C08/2013 (H9N9) shows that the hemagglutinin (HA) genes of this strain are closely related to those of the strain A/chicken/Shanghai/1107/2013 (H9N2) and share 99.2% nucleotide homology, while the other seven genes had the greatest sequence identities with the novel H7N9 virus. We speculate that this strain may be a novel natural reassortant...

Live poultry markets are a source of human infection with avian influenza A (H7N9) virus. On February 21, 2014, a poultry farmer infected with H7N9 virus was identified in Jilin, China, and H7N9 and H9N2 viruses were isolated from the patient's farm. Reassortment between these subtype viruses generated five genotypes, one of which caused the human infection. The date of H7N9 virus introduction ...

Neuraminidase (NA), a structural protein of the H9N2 avian influenza virus (H9N2 AIV), can facilitate viral invasion of the upper airway by cleaving the sialic acid moieties on mucin. Dendritic cells (DCs) are major antigen-presenting cells whose immune functions, such as presenting antigens and activating lymphocytes, can be regulated by microRNAs. Here, we studied the molecular mechanism of m...