动物造模 z-bio 2022-01-22 435

　　Purpose: After the highly pathogenic avian influenza infects mice, the over-expressed inflammatory factors, namely inflammatory factor storm, are detected in the lungs. High-level inflammatory responses are more common in elderly infected persons. This article explores the effects of inflammatory storms in the lungs of elderly hosts. Influence of anti-infective immune response.

　　Methods: Aged mice (18-24 months old) were challenged with influenza virus H9N2 to establish an old mouse infection model. The control group was H9N2 infected adult mice (6-8 weeks). H9N2 infection was quantitatively analyzed. The expression of inflammatory factors in the lung in situ and peripheral blood of old mice, and during the acute phase of infection, the collected mouse lung tissues were prepared into slices and digested into single-cell suspensions. Among them, lung tissue slices were used Immunohistochemistry in situ quantitative analysis of immune cell distribution; T cells were sorted out from the cell suspension and stained and counted.

　　Results: Compared with adult mice, aged mice were infected with H9N2 virus, their body weight decreased significantly, and the survival rate was only 50%. However, compared with adult mice that rarely detected inflammatory factors in lung tissue after infection, old mice Inflammatory factor storms appear in the lungs, inflammatory factor IL-6 and chemokine MCP-1 are abnormally high expression, and reach a peak value (over 4000pg/mL) on the second day after infection, which is 100~1000 times that of adult control mice. After being infected with H9N2 virus, old mice have lower response of lung macrophages and weaker migration ability of lung neutrophils compared with adult controls, and they stay in the lungs more in the 3-7 days after infection. , On the 7th day after H9N2 infection in old mice, the number of CD8+ T cells in the lungs decreased significantly, and the number and proportion of CD4+ T cells remained normal.

　　Conclusion: The lung tissue of old mice infected with H9N2 virus has a storm of inflammatory factors. Although the types of cells involved in the anti-infection immune response are not significantly different from those of adult mice, the migration ability of immune cells is reduced, and the acquired cellular immunity involved in the response is also strong. Significantly reduced.