Project description:Human rhinovirus and influenza virus infections of the upper airway lead to colds and the flu and can trigger exacerbations of lower airway diseases including asthma and chronic obstructive pulmonary disease. Despite modest advances in the diagnosis and treatment of infections by these viruses, novel diagnostic and therapeutic targets are still needed to differentiate between the cold and the flu, since the clinical course of influenza can be severe while that of rhinovirus is usually more mild. In our investigation of influenza and rhinovirus infection of human respiratory epithelial cells, we used a systems approach to identify the temporally changing patterns of host gene expression from these viruses. After infection of human bronchial epithelial cells (BEAS-2B) with rhinovirus, influenza virus or co-infection with both viruses, we studied the time-course of host gene expression changes over three days. From these data, we constructed a transcriptional regulatory network model that revealed shared and unique host responses to these viral infections such that after a lag of 4-8 hours, most cell host responses were similar for both viruses, while divergent host cell responses appeared after 24-48 hours. The similarities and differences in gene expression after epithelial infection of rhinovirus, influenza virus, or both viruses together revealed qualitative and quantitative differences in innate immune activation and regulation. These differences help explain the generally mild outcome of rhinovirus infections compared to influenza infections which can be much more severe. Human bronchial epithelial cells (BEAS-2B) were infected with rhinovirus, influenza virus or both viruses and RNAs were then profiled at 10 time points (2, 4, 6, 8, 12, 24, 26, 48, 60 and 72hrs)
Project description:Human rhinovirus and influenza virus infections of the upper airway lead to colds and the flu and can trigger exacerbations of lower airway diseases including asthma and chronic obstructive pulmonary disease. Despite modest advances in the diagnosis and treatment of infections by these viruses, novel diagnostic and therapeutic targets are still needed to differentiate between the cold and the flu, since the clinical course of influenza can be severe while that of rhinovirus is usually more mild. In our investigation of influenza and rhinovirus infection of human respiratory epithelial cells, we used a systems approach to identify the temporally changing patterns of host gene expression from these viruses. After infection of human bronchial epithelial cells (BEAS-2B) with rhinovirus, influenza virus or co-infection with both viruses, we studied the time-course of host gene expression changes over three days. From these data, we constructed a transcriptional regulatory network model that revealed shared and unique host responses to these viral infections such that after a lag of 4-8 hours, most cell host responses were similar for both viruses, while divergent host cell responses appeared after 24-48 hours. The similarities and differences in gene expression after epithelial infection of rhinovirus, influenza virus, or both viruses together revealed qualitative and quantitative differences in innate immune activation and regulation. These differences help explain the generally mild outcome of rhinovirus infections compared to influenza infections which can be much more severe.
Project description:Viral infection perturbs host cells and can be used to uncover host regulatory mechanisms controlling both cell response and homeostasis. Here, using cell biological, biochemical and genetic tools, we reveal that influenza virus infection induces global transcriptional defects at the 3’-end of active host genes and RNA polymerase II (RNAPII) run-through into extragenic regions. This effect induces the biogenesis of aberrant RNAs (3’-extensions and host gene fusions) which ultimately causes global transcriptional downregulation of physiological transcripts, an effect that impacts antiviral response and virulence. We show that this phenomenon occurs with multiple strains of influenza virus and it is dependent on influenza NS1 protein expression. Mechanistically, pervasive RNAPII run-through can be modulated by SUMOylation of an intrinsically disordered region (IDR) of the NS1 expressed by the 1918 pandemic influenza virus. SUMOylation increases NS1 partitioning in nuclear granules and interference with the host transcriptional apparatus which result in augmentation of termination defects and a concomitant increase in global host gene shut off. Our data identify a general strategy used by influenza virus to suppress host gene expression and indicate that polymorphisms in IDRs of viral proteins, along with human genetic variation in enzymes that metabolize post-translational modifications, can determine the outcome of an infection. We thus propose that analysis of strain-specific determinant of pathogenesis can shed light on the molecular basis of virulence.
Project description:Whole-genome, time-course data was developed from the lungs of influenza infected mice to better characterize the dynamics of the host immune response during infection.
Project description:As a mild, highly contagious, respiratory disease, swine influenza always damages the innate immune systems, and increases susceptibility to secondary infections which results in considerable morbidity and mortality in pigs. Nevertheless, the systematical host response of pigs to swine influenza virus infection remains largely unknown. To explore these, a time-course gene expression profiling was performed to detect comprehensive analysis of the global host response induced by H1N1 swine influenza virus in pigs.
Project description:Our understanding of the synergism between S. pneumoniae and influenza virus remains incomplete. The classic dogma has been that influenza attenuates the host innate immunity and increase the susceptibility to subsequent bacterial infection. Therefore, the majority of current studies have been focusing on the interaction of S. pneumoniae and influenza in the context of host cells. By contrast, in this study, we set out to investigate the response of pneumococcus alone to virus infection. Our hypothesis was that prior to causing any damages to host cells, influenza may have induced (lethal) changes to pneumococcus cell itself. Indeed, a very recent evidence has shown that direct viral treatment to pneumococcus will increase its adhesion to macrophage cells. Here, using quantitative phosphoproteomic approach, we attempt to investigate the global alterations of S. pneumoniae phosphorylation by influenza virus challenge, and provide a landscape of synergism between the IAV and pneumococcus.