Role Of Type Ⅱ Innate Lymphocytes In A Mouse Model Of Pseudomonas Aeruginosa Infection

Objective: This study aims to investigate the role of exogenous Type 2 innate lymphocytes(ILC2)in inflammation,immunity,and tissue repair,in order to provide theoretical support for elucidating their role and achieving cell therapy related diseases.Method: 1.Enrich ILC2 by intraperitoneal injection of interleukin-33(IL-33),then screen for ILC2 using magnetic beads,and perform flow cytometry for flow cytometry to determine the screening efficiency.2.A mouse model of pulmonary infection caused by Pseudomonas aeruginosa(PA)was constructed by nasal and airway instillation.The number of neutrophils in the alveolar lavage fluid was observed by smear analysis,the expression of different serum inflammatory factors was detected by ELISA detection kit,the expression of inflammatory factors in lung tissue was detected by real-time quantitative PCR technology,and lung tissue damage was observed by HE staining To evaluate the successful establishment of a mouse pneumonia model infected with Pseudomonas aeruginosa,lung tissue and alveolar lavage fluid were smeared to observe lung bacterial load.3.After 6 hours of bacterial infection,the selected ILC2 was infused back into mice through the tail vein and divided into three groups: the copper green model group,the physiological saline infused group,and the ILC2 infused group.After 48 hours,samples were taken and the number of neutrophils in the alveolar lavage fluid was observed through lung lavage fluid smear.The expression of serum inflammatory factor IL-6was detected using an ELISA test kit,and lung lesions were observed through HE staining of lung tissue.Result: 1.ILC2 was successfully screened through magnetic beads.2.A mouse lung infection model of Pseudomonas aeruginosa was successfully established through airway infusion.3.The results of bronchoalveolar lavage fluid smear showed a significant decrease in neutrophils in the ILC2 reinfusion group,with a statistically significant difference(P<0.001).4.The results of serum inflammatory factor IL-6 showed that the IL-6 expression was the lowest in the ILC2 reinfusion group,and the difference was statistically significant(P<0.01).5.The HE results of lung tissue showed a significant reduction in lung tissue damage in the ILC2 reinfusion group.Conclusion: 1.Enriching ILC2 by intraperitoneal injection of IL-33,and then using magnetic bead sorting,high purity ILC2 can be obtained,which can be directly used for cell transfusion;2.The bacterial colonization of mice through nasal and airway instillation can effectively establish a mouse lung infection model.In this experiment,the mouse lung infection model induced by airway instillation of bacteria was superior to nasal instillation;3.The tail vein infusion of ILC2 can effectively alleviate the pulmonary inflammatory response and tissue damage caused by Pseudomonas aeruginosa infection in mice.