Project description:Using human umbilical vein endothelial cells (HUVECs) as cell models, the present study aims to explore the differential miRNAs in influenza virus-infected ECs and analyze their target genes involved in EC permeability regulation. As the results showed, permeability increased and F-actin cytoskeleton reorganized after HUVECs infected with influenza A virus (CA07 or PR8) at 30 MOI. most of these miRNAs were down-regulated after flu infection. It has been reported that PKC, Rho/ROCK, HRas/Raf/MEK/ERK, and Ca2+/CaM pathways are activated by flu infection and play important roles in permeability regulation.
Project description:To delineate specific patterns of signaling networks activated by H5N1 we used a comparative systems biology approach analyzing gene expression in endothelial cells infected with three different human and avian influenza strains of high and low pathogenicity. HUVECs were infected with either PR8, FPV or H5N1 virus. We used wildtype HUVEC or HUVEC transfected with a dominant negative mutant of IKK2 (block of the NF-kB signaling pathway).
Project description:To further understand the molecular pathogenesis of the 2009 pandemic H1N1 influenza virus infection, we profiled cellular miRNAs of lung tissue from BALB/c mice infected with influenza virus BJ501 and a mouse-adapted influenza virus A/Puerto Rico/8/34 (H1N1)(PR8) as a comparison.
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:Macrophages were infected with low (PR8) and high pathogenic influenza viruses (FPV and H5N1). To our surprise a genome-wide comparative systems biology approach revealed that in contrast PR8 infections with HPAIV H5N1 and FPV result in a reduced immune response of human macrophages contradicting a primary role of this cell type for the cytokine storm. Our data point to a viral strategy of HPAIV to bypass a major amplifier of the initial local inflammatory response thereby hampering antiviral effector mechanisms and facilitating virus spreading and systemic disease. Macrophages were infected with low (PR8) and high pathogenic influenza viruses (FPV and H5N1)
Project description:Array analysis of total RNA from broncho-alveolar lavage (BAL) from mice infected with influenza virus (PR8) and/or Staphylococcus aureus (Newman)
Project description:To further understand the molecular pathogenesis of the 2009 pandemic H1N1 influenza virus infection, we profiled cellular miRNAs of lung tissue from BALB/c mice infected with influenza virus BJ501 and a mouse-adapted influenza virus A/Puerto Rico/8/34 (H1N1)(PR8) as a comparison. Five groups of mice were selected, and three of each group were used to profile the miRNA, two were in case for unqualified RNA extraction. Whole lungs from mice infected by BJ501 or PR8 were harvested on 2,5 days post infection (dpi), and compared with lung samples from 5 uninfected mice.
Project description:DBA/2J (D2) and C57BL/6J mice (B6) were infected intra-nasally with 2x10^3 FFU of influenza A H1N1 (PR8) virus. Lungs were collected from mock-infected controls or at day 1,2,3,4 post infection. Expression data were obtained from three independent experiments. We infected a highly susceptible mouse strain (D2) and a resistant strain (B6) with PR8 and performed a genome-wide expression analysis. We found genes expressed in lung epithelium that were specifically down-regulated in D2 mice, whereas a cluster of genes on chromosome 3 was only down-regulated in B6. In both mouse strains, chemokines, cytokines and interferon-response genes were up-regulated, indicating that the main innate immune defense pathways were activated. However, many immune response genes were up-regulated in D2 much stronger than in B6, and several immune response genes were exclusively regulated in D2. Thus, susceptible D2 mice showed a hyper-inflammatory response. This response is similar to infections with highly pathogenic influenza virus and may serve as a paradigm for a hyper-inflammatory host response to influenza A virus.
Project description:Influenza A virus induces host shutoff mainly through its endoribonuclease PA-X. Like many host shutoff nucleases, PA-X activity affects different host RNAs to varying degrees. To understand how PA-X discriminates between different mRNAs, we took a high-throughput approach to directly identify PA-X cut sites transcriptome-wide and examine PA-X cleavage characteristics. To do this, we compared RNA fragments from mock infected cells to cells infected with the wild-type (WT) A/PuertoRico/8/1934 H1N1 (PR8) influenza virus strain, or the same strain engineered to lack PA-X, referred to as PR8-PA(∆X).
