【Animal Modeling】-TNF-α humanized mouse model of Listeria monocytogenes infection

  Purpose: To evaluate the change of the host's susceptibility to Listeria monocytogenes infection after drug intervention with TNF-α monoclonal antibody.

  Method: The animals were divided into C57BL/6 mice infection control group, TNF-α humanized mouse infection control group, and TNF-α humanized mouse adalimumab intervention group (n = 6). The mice in the control group were intravenously injected with 200 μL of normal saline 24 hours before infection, and the mice in the adalimumab group were injected with 200 μL of adalimumab intravenously at 10 mg/kg 24 hours before infection. After intraperitoneal inoculation of Listeria monocytogenes 1×104 CFU, the amount of bacteria in the liver and spleen tissues, pathological changes and the distribution of immune cells were detected, and the differences between the control group and the antibody intervention group were counted. Results: After 4 days of infection with Listeria monocytogenes, the area of microabscesses in the liver of mice in the antibody intervention group increased significantly (P<0.05), and the bacterial load in the spleen and liver tissues increased significantly compared with the control mice. (P <0.01), while the distribution of macrophages and B cells did not change significantly.

   Conclusion: TNF-α plays an important role in the host's immunity against Listeria monocytogenes, and the host disease progression is significantly worse after the intervention of TNF-α monoclonal antibody.