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:To study the effects of secondary bacterial infection during 1918 pandemic H1N1 influenza virus infection, BALB/c mice were inoculated with the fully reconstructed 1918 influenza virus followed by inoculation with pneumococcus 72h later. To study the effects of secondary bacterial infection during 1918 pandemic H1N1 influenza virus infection, BALB/c mice were inoculated with the fully reconstructed 1918 influenza virus followed by inoculation with pneumococcus 72h later.
Project description:This study used virological, histological, immunological and global gene expression to compare the virlence of two newly emerged 2009 H1N1 isolates (A/Mexico/InDRE4487/2009 and A/Mexico/4108/2009) and current seasonal H1N1 influenza strain (A/Kawasaki/UTK-4/2009) in experimentally infected cynomolgus macaques. We showed that infection of macaques with two genetically similar but clinically distinct SOIV isolates from the early stage of the pandemic (A/Mexico/4108/2009 and A/Mexico/InDRE4487/2009) resulted in upper and lower respiratory tract infections and clinical disease ranging from mild to severe pneumonia. Disease associated with these SOIV isolates was clearly advanced over the mild infection caused by A/Kawasaki/UTK-4/2009, a current seasonal strain. Total dose of 7 x 10^6 pfu of influenza virus by a combination of different routes: intratracheal (4 ml), intranasal (0.5 ml each nostril), intraocular (0.5 ml each eye), and oral (1 ml).
Project description:The 1918 influenza pandemic was unusually severe, resulting in about 50 million deaths worldwide. A reconstructed version of the 1918 (H1N1) virus has been shown to also highly pathogenic in mice; however, the potential virulence and pathogenicity of the 1918 virus in nonhuman primates in unknown. In these studies, we demonstrate that the 1918 virus caused a highly pathogenic respiratory infection in a cynomolgus macaque model that culminated in acute respiratory distress and a fatal outcome. To characterize the global gene expression host response, oligonulceotide microarray analysis was performed on RNA isolated from the bronchus of macaques infected with either the 1918 virus or a humanized contemporary H1N1 influenza virus (A/Kawasaki/173/01). These experiments showed that infected animals mounted an immune response, characterized by dysregulation of the antiviral response, that was insufficient for protection, suggesting that atypical host innate immune responses may contribute to lethality.
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:Periodic outbreaks of highly pathogenic avian H5N1 influenza viruses and the current H1N1 pandemic highlight the need for a more detailed understanding of influenza virus pathogenesis. To investigate the host transcriptional response induced by pathogenic influenza viruses, we used a functional-genomics approach to compare gene expression profiles in lungs from wild-type 129S6/SvEv and interferon receptor (IFNR) knockout mice infected with either the fully reconstructed H1N1 1918 pandemic virus (1918) or the highly pathogenic avian H5N1 virus Vietnam/1203/04 (VN/1203).
Project description:To study the effects of secondary bacterial infection during 1918 pandemic H1N1 influenza virus infection, BALB/c mice were inoculated with the fully reconstructed 1918 influenza virus followed by inoculation with pneumococcus 72h later.
Project description:The influenza A(H1N1)pdm09 virus caused a global flu pandemic in 2009 and contributes to seasonal epidemics. Different treatment and prevention options for influenza have been developed and applied with limited success. Here we report that an Akt inhibitor MK2206 possesses potent antiviral activity against influenza A(H1N1)pdm09 virus in vitro. We showed that MK2206 blocks the entry of different A(H1N1)pdm09 strains into cells. Moreover, MK2206 prevented A(H1N1)pdm09-mediated activation of cellular signaling pathways and the development of cellular immune responses. Importantly, A(H1N1)pdm09 virus was unable to develop resistance to MK2206. Thus, MK2206 is a potent anti-influenza A(H1N1)pdm09 agent.
Project description:The influenza A(H1N1)pdm09 virus caused a global flu pandemic in 2009 and contributes to seasonal epidemics. Different treatment and prevention options for influenza have been developed and applied with limited success. Here we report that an Akt inhibitor MK2206 possesses potent antiviral activity against influenza A(H1N1)pdm09 virus in vitro. We showed that MK2206 blocks the entry of different A(H1N1)pdm09 strains into cells. Moreover, MK2206 prevented A(H1N1)pdm09-mediated activation of cellular signaling pathways and the development of cellular immune responses. Importantly, A(H1N1)pdm09 virus was unable to develop resistance to MK2206. Thus, MK2206 is a potent anti-influenza A(H1N1)pdm09 agent. Total RNA obtained from NCI-H1666 cells, which are non-small cell lung cancer cell line. NCI-H1666 cells were non- or MK2206-treated (10 μM) and mock- or virus-infected (A/Helsinki/p14/2009) at moi of 3.
Project description:Targeting cell death pathways, including pyroptosis and necroptosis, has been shown to mitigate influenza virus infection severity. Here, we examined whether pyroptosis specifically driven by the pore-forming protein gasdermin E (GSDME) is involved in regulating influenza virus infection outcomes. We found that Gsdme-/- mice showed similar weight loss and survival in severe A/PR/8/34 (H1N1) virus infections compared to WT counterparts. Likewise, lung dysfunction, histopathological damage, viral titers, and inflammatory cytokine levels were similar in the two groups. Global transcriptomic analysis also revealed similar gene expression programs in WT versus Gsdme-/- mouse lungs at baseline and in response to infection. To confirm the generality of these findings, we infected mice with 2009 pandemic H1N1 virus and again observed similar weight loss, mortality, and lung dysfunction in WT and Gsdme-/- mice. Our results overall demonstrate that GSDME contributes negligibly to the host response against H1N1 influenza virus, refining our understanding of cell death pathways in influenza pathogenesis.
