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:The determinants of influenza transmission remain poorly understood. Swine influenza viruses preferentially attach to receptors found in the upper airways; however, most swine influenza viruses fail to transmit efficiently from swine to humans, and from human-to-human. The pandemic 2009 H1N1 (H1N1pdm) virus was a rare exception of a swine virus that acquired efficient transmissibility from human-to-human, and is reflected in efficient respiratory droplet transmission in ferrets. We hypothesize that virus-induced host responses in the upper airways correlate with airborne transmission in ferrets. To address this question, we used the H1N1pdm virus and swine influenza A/swine/Hong Kong/201/2010 (HK201) virus that has comparable titre in the ferret nasopharynx, but it exhibits differential transmissibility in ferrets via respiratory droplet route. We performed a transcriptomic analysis of tissues from the upper and lower respiratory tract from ferrets infected with either H1N1pdm or HK201 viruses using ferret-specific Agilent oligonucleotide arrays. We found differences in the kinetics of the innate immune response elicited by these two viruses that varied across tissues.
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)