【Animal Modeling】-The effect of inflammatory factor storm on immune response to infection in aged mice

  Purpose: After infecting mice with highly pathogenic avian influenza, are over-expressed inflammatory factors or inflammatory factor storms detected in the lungs? Is high inflammation more common in older people infected? In this article, we explored the impact of inflammatory storms in the lungs of elderly hosts: the impact of anti-infection immune response?

  Method: Have you used old mice (18-24 months) to challenge influenza virus H9N2 to establish an old mouse infection model? Is the control group an adult mouse (6-8 weeks) infected with H9N2? We quantitatively analyzed the expression of inflammatory factors in the lung and peripheral blood of H9N2 infected aging mice. During the acute phase of infection, the collected lung tissues of the mice were sliced and digested into single cell suspension. Among them, lung tissue sections are used for immunohistochemical in situ quantitative analysis of immunocytochemical distribution; whether to sort, stain and count T cells from cell suspension?

  Result: Compared with adult mice, older mice after being infected with H9N2 virus have lost significant weight, and their survival rate is only 50%? However, compared with several inflammatory factors found in the lung tissues of adult mice after infection, inflammatory factors, inflammatory factors IL-6 and inflammatory factor storms appeared in the lungs of elderly mice . The chemokine MCP-1 expression is abnormally high, reaching a peak level (\→ 4000 pg/mL) 2 days after infection. This is 100 to 1000 times that of adult control mice. Compared with the adult control group, elderly mice infected with H9N2 virus have lower lung macrophage response, weaker lung neutrophil migration ability and more lung retention 3-7 days after infection? Moreover, in old mice, 7 days after H9N2 infection, the number and proportion of lung CD8 + T cells decreased significantly, while the number and proportion of CD4 + T cells remained normal?

  Conclusion: After H9N2 virus is infected with H9N2 virus, is there an inflammatory factor storm in the lung tissue of aging mice? There is no big difference, but the migration ability of immune cells will be reduced, and the acquired cellular immunity involved in the response will also be greatly reduced?