Project description:The pathogenesis of avian influenza A H5N1 virus in human has not been clearly elucidated. There have been increasing evidence suggesting a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. However, the role of aberrant innate immune response in human lungs infected by avian influenza H5N1 virus has not been explored and direct evidence for inappropriate innate responses in lungs of avian influenza H5N1 virus infected patients is lacking.
Project description:The pathogenesis of avian influenza A H5N1 virus in human has not been clearly elucidated. There have been increasing evidence suggesting a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. However, the role of aberrant innate immune response in human lungs infected by avian influenza H5N1 virus has not been explored and direct evidence for inappropriate innate responses in lungs of avian influenza H5N1 virus infected patients is lacking. In order to obtain evidences for the proposed role of aberrant innate immune response in avian influenza H5N1 virus pathogenesis in human, we analyzed expression profile of lung tissues from two fatal cases of avian influenza H5N1 virus infected patients in comparison to normal human lung using an expression microarray.
Project description:The H5N1 avian influenza virus clade 2.3.4.4b outbreak represents a major pandemic threat for humans. Although most human cases to date have been mild, several severe cases of respiratory illness have been reported. A key unanswered question is the pathogenesis of H5N1 infection in primates following respiratory infection. In this study, we observed severe clinical disease in cynomolgus and rhesus macaques following respiratory infection with the H5N1 isolate A/Texas/37/2024 (hu-TX37-H5N1). Cynomolgus macaques inoculated with a high dose of hu-TX37-H5N1 developed severe consolidative necrotizing pneumonia with extrapulmonary spread. Clinical disease was rapidly progressive and lethal in 100% (9 of 9) of macaques by day 5-9 following challenge. Rhesus macaques inoculated with varying doses of hu-TX37-H5N1 demonstrated dose-dependent mortality, and surviving animals showed robust natural protective immunity against high dose re-challenge. H5N1 infection in both cynomolgus and rhesus macaques was characterized by upregulation of proinflammatory cytokine, innate immune cell, complement and coagulation, apoptosis, and immune exhaustion pathways and downregulation of NK, T, and B cell activation and differentiation pathways. Taken together, our data demonstrate severe respiratory disease with H5N1 clade 2.3.4.4b in nonhuman primates and suggest that acute inflammation and immune dysregulation are key contributors to disease pathogenesis.
Project description:To study miRNA expression profiles during highly pathogenic avian influenza virus infection, we conducted global miRNA expression profiling in human lung epithelial cells (A549) with or without H5N1 IAV infection. .
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:Transcriptional profiling was carried out on lung and ileum samples at 1dpi and 3dpi from chickens infected with either low pathogenic (H5N2) or highly pathogenic (H5N1) avian influenza. Infected birds were compared to control birds at each time point.
Project description:Transcriptional profiling was carried out on lung and ileum samples at 1dpi and 3dpi from ducks infected with either low pathogenic (H5N2) or highly pathogenic (H5N1) avian influenza. Infected birds were compared to control birds at each time point.
Project description:Transcriptional profiling was carried out on lung and ileum samples at 1dpi and 3dpi from quail infected with either low pathogenic (H5N2) or highly pathogenic (H5N1) avian influenza. Infected birds were compared to control birds at each time point.