动物造模 z-bio 2022-11-22 290

　　Objective: To establish a mouse model of systemic infection with methicillin-resistant Staphylococcus aureus (MRSA) in ICR mice.

　　Methods: After immunosuppression by intraperitoneal injection of cyclophosphamide (100 mg/kg) for 3 consecutive days × The ICR mice were inoculated with 107 cfu/mL MRSA bacterial solution via tail vein. The model was evaluated by survival analysis, peripheral blood leukocyte count, tissue bacterial load and pathological examination.

　　Results: The mice began to die on the second day after inoculation with MRSA, and the cumulative mortality reached 60% within 14 days; The total number of white blood cells in peripheral blood increased significantly. Bacteria were colonized in multiple organs. The bacterial load from high to low was kidney, joint, lung, liver and brain. The bacterial load in kidney was up to 109 CFU/g, and the bacterial load in joint, lung, liver and brain ranged from 104 to 109 CFU/g. Pathological observation showed the histopathological changes of kidney, heart, lung, liver, brain and joint infection.

　　Conclusion: The mouse model of systemic infection with MRSA was successfully established by intravenous injection of MRSA after cyclophosphamide immunosuppression. This model can be used in the research fields of pathogenesis and drug screening of MRSA.