Objective: To study the histopathological changes and virus content changes in commonly used laboratory mice after norovirus artificial infection.
Method: Using 5 mouse strains KM, BALB/c, NIH, C57BL/6, BALB/c-nu, each strain was divided into a control group and an infected group, and the bastard of the infected group was forcibly fed. .. Virus solution (control group) was filled with the same amount of normal saline, and liver, spleen, lung, cecum, colon and small intestine were collected on the 7, 14, 21, 28 and 55 days after infection. Take two copies of each tissue for pathological diagnosis. Then detect the nucleic acid content of the virus, and finally summarize and analyze the results.
Result: The total incidence of pathological changes in the liver, spleen and lungs were 8% (10/125), 5.6% (7/125) and 4% (5/125), respectively. No lesions were found in the cecum, colon or small intestine. The lesions of KM and BALB/c mice mainly occurred in the liver, spleen and lungs, C57BL/6 mice were mainly located in the liver and lungs, while NIH and BALB/c-nu mice were mainly located in the liver and spleen. Yes. Among the observed experimental mice, KM mice are more prone to lung lesions, KM and NIH mice are more prone to lesions, and C57BL/6 mice appear later. In all experimental mice, the positive rates of MNV nucleic acid in the cecum and colon were 100% (125/125), and the positive rates of small intestine, liver, spleen, lung and blood were 71.2% (89/125) and 17.6%, respectively (17.6%). 22/125), then 39.2,% (49/125), 3.2% (4/125) and 1.6% (2/125); comparison of virus content in cecum, colon, small intestine, lung and liver; BALB/c -nu mouse colon virus content is significantly higher. Compared with other strains of mice, the virus content of each tissue of other strains of mice is not statistically different (P\u003c0.01); C57BL/6 mice The highest serum and colon virus content (P\u003c0.05) was reached on the 14th day of MNV infection. There was no statistical difference in the virus content of mice of other strains at different time points. Yes; there is no correlation between the results of pathological examination of tissues and organs and the detection of viral nucleic acid.
Conclusion: Norovirus infection in mice can cause tissue damage. It is recommended to select MNV-negative mice for pathological animal experiments.