【Animal Modeling】-Systematic Evaluation of Animal Models of Inflammation Induced by Atmospheric Fine Particulate Matter

  OBJECTIVE: To explore the pathogenic mechanism of air pollution on animals, and to construct an animal model of air pollution-induced inflammation by non-invasive tracheal instillation of PM2.5 particle suspension in BALB/c mice.

  Methods: 150 SPF grade BALB/c mice were randomly divided into blank control group, saline group, PM2.5 low group (2.5 mg/kg), PM2.5 moderate group (5 mg/kg) and PM2. 5 height groups (10 mg/kg), a total of 5 groups, each dose group received tracheal instillation on the 3rd day, the 7th day, the 21st day, the 35th day and the 49th day, and tissue samples were taken 24 hours after the tracheal instillation operation was completed. , Using ELISA? Lung tissue pathological HE staining method to verify the feasibility of the non-invasive tracheal instillation method and the establishment of the inflammatory model successfully?

  Results: The success rate of this modeling method was as high as 96%? Using the tracheal instillation method, the lung tissue inflammation score of the modeling mice was positively correlated with the prolongation of airway instillation time and the dose? After PM2. Lymphocyte aggregation and macrophage infiltration of phagocytosed particles, widening of alveolar septum? Compared with normal saline control group? The level increased, and the difference in the high-dose group was the most significant?

  Conclusion: In this experiment, the tracheal instillation method was successfully used to establish a mouse model of inflammation, and it was proved that this method is simple and reliable, and can be widely used for repeated instillation in the respiratory system of mice, which is conducive to further research on air pollution and other inflammatory mechanisms.