Studies On Antigen Localization And Gene Differential Expression In Avian Influenza Virus Infected Chicken

Avian influenza (AI) is a fatal syndrome caused by avian influenza virus (AIV), which leads mainly to the general or respiratory infectious disease of avian. Recently, the prevalence of AI is more and more severe. From the year of 2003 to now, it has spread to Europe and Africa from Asia. Since the infection of human being by AIV in Hong Kong in 1997, there have been nearly one hundred people dieing of AIV infection. Scientists predict that the pandemic of the AI may possibly result in the outbreak of human being's influenza. At present, the hot spot of the AI research is focused on the cloning of viral gene, the detection method of virus and development of vaccine, and so on. However, there are few reports involved in the fundamental research of AI. Up to now, the research of the pathogenic mechanism of AIV in its natural host chicken is still limited to tissue and cell levels. Much research work about the responsive mechanism of host during the course of infection, the molecular mechanism of the rapid death of animal, the proteins interaction between host and virus, and the distribution of different subtype ATV in host is remained not carried out. To elucidate the pathogenic mechanism of AIV in chicken is not only helpful to prevent and cure the infection of AIV in animal, but also significant to understand the infection mechanism of AIV in human being. The work of this dissertation is involved in the distribution of ATV in chicken, the differential expression of chicken genes during AIV infection, and the interaction between host proteins and viral protein. The results of the research are as follows:1 Development of in situ hybridization (ISH) assay for detection of AIV in MDCK cellA model of viral infection is set up, by infecting MDCK cell with ATV. A 543 bp fragment of AIV NP gene is amplified by RT-PCR, and then DIG -labeled as the probe of ISH. Through optimizing different conditions, ISH assay for detection of AIV in infected MDCK cell has been established, which has such advantages as high specificity, strong sensitivity, and good repeatability. This method can enable us to probe the exact localization of ATV, and further investigate the pathogenic mechanism.2 Localization of avian influenza virus within chicken tissuesBy using AIV to infect chicken, a pathologic model is established. Prepare paraffin sections of different tissues of infected chicken. Then ISH is used for detecting AIV within these tissues. The result shows that, the low pathogenic H9N2 subtype AIV is localized at the epithelial cells of duodenum villus and that of alveolar wall, as well as the matrix of cartilage of throat and trachea post-infection, and the appearance of AIV within...