Project description:Chicken brain and lung gene expression profiles following infection with two recombinant H5N3 avian influenza viruses - rH5N3 Ori (P0) and rH5N3 P6
Project description:H5N1 subtype highly pathogenic avian influenza virus has been spreading to Asia, Eurasia and African coutries. An original or six of recombinant H5N1 subtype influenza viruses with varying survivability were infected to chickens for elucidating genes correlated with pathogenicity.
Project description:H5N1 subtype highly pathogenic avian influenza virus has been spreading to Asia, Eurasia and African coutries. An original or six of recombinant H5N1 subtype influenza viruses with varying survivability were infected to chickens for elucidating genes correlated with pathogenicity. Two chickens were infected with each 10^6EID50/ head virus intranasally, and their lung was collected from infected chicken at 24 hours after infection.
Project description:In recent years, the roles of microRNAs playing in the regulation of influenza viruses replication caused researchers' much attenion. However, much work focused on the interactions between human, mice or chicken microRNAs with human or avian influenza viruses rather than the interactions of swine microRNAs and swine influenza viruses. To investigate the roles of swine microRNAs playing in the regulation of swine influenza A virus replication, the microRNA microarray was performed to identify which swine microRNAs were involved in swine H1N1/2009 influenza A virus infection.
Project description:Highly pathogenic influenza virus inhibit Inflammatory Responses in Monocytes via Activation of the Rar-Related Orphan Receptor Alpha (RORalpha). Low (PR8) and high pathogenic influenza viruses (FPV and H5N1) were used. Monocytes were infected with low (PR8) and high pathogenic influenza viruses (FPV and H5N1)
Project description:Zoonotic influenza A viruses of avian origin can cause severe disease in individuals, or even global pandemics, and thus pose a threat to human populations. Waterfowl and shorebirds are believed to be the reservoir for all influenza A viruses, but this has recently been challenged by the identification of novel influenza A viruses in bats. The major bat influenza A virus envelope glycoprotein, haemagglutinin, does not bind the canonical influenza A virus receptor, sialic acid or any other glycan, despite its high sequence and structural homology with conventional haemagglutinins. This functionally uncharacterized plasticity of the bat influenza A virus haemagglutinin means the tropism and zoonotic potential of these viruses has not been fully determined. Here we show, using transcriptomic profiling of susceptible versus non-susceptible cells in combination with genome-wide CRISPR-Cas9 screening, that the major histocompatibility complex class II (MHC-II) human leukocyte antigen DR isotype (HLA-DR) is an essential entry determinant for bat influenza A viruses. Genetic ablation of the HLA-DR α-chain rendered cells resistant to infection by bat influenza A virus, whereas ectopic expression of the HLA-DR complex in non-susceptible cells conferred susceptibility. Expression of MHC-II from different bat species, pigs, mice or chickens also conferred susceptibility to infection. Notably, the infection of mice with bat influenza A virus resulted in robust virus replication in the upper respiratory tract, whereas mice deficient for MHC-II were resistant. Collectively, our data identify MHC-II as a crucial entry mediator for bat influenza A viruses in multiple species, which permits a broad vertebrate tropism.
Project description:Influenza B virus (IBV) strains are one of the components of seasonal influenza vaccines in both trivalent and quadrivalent formulations. The vast majority of these vaccines are produced in embryonated chickens' eggs. While optimized backbones for vaccine production in eggs exist and are in use for influenza A viruses, no such backbones exist for IBVs, resulting in unpredictable production yields. To generate an optimal vaccine seed virus backbone, we have compiled a panel of 71 IBV strains from 1940 to present day, representing the known temporal and genetic variability of IBV circulating in humans. This panel contains strains from the B/Victoria/2/87-like lineage, B/Yamagata/16/88-like lineage and the ancestral lineage that preceded their split to provide a diverse set that would help to identify a suitable backbone which can be used in combination with hemagglutinin (HA) and neuraminidase (NA) glycoproteins from any IBV strain to be incorporated into the seasonal vaccine. We have characterized and ranked the growth profiles of the 71 IBV strains and the best performing strains were used for co-infection of eggs, followed by serial passaging to select for high-growth reassortant viruses. After serial passaging, we selected 10 clonal isolates based on their growth profiles assessed by hemagglutination and plaque-forming units. We then generated reverse genetics systems for the three clones that performed best in growth curves. The selected backbones were then used to generate different reassortant viruses with HA/NA combinations from high and low titer yielding wild type IBV. When the growth profiles of the recombinant reassortant viruses were tested, the low titer yielding HA/NA viruses with the selected backbones yielded higher titers similar to those from high titer yielding HA/NA combinations. The use of these IBV backbones with improved replication in eggs might increase yields for the influenza B virus components of seasonal influenza virus vaccines.