动物造模 z-bio 2022-11-22 305

　　Objective: To establish a systemic infection model by oral infection of ICR mice with C. albicans, and observe the tissue proliferation and distribution of C. albicans in mice after mucosal infection.

　　Methods: 46 male ICR mice were randomly divided into model group A (n=20), model group B (n=20) and control group (n=6). The model group was orally inoculated with C albicans（7 × 106 cfu/mL), the control group was inoculated with equal volume of normal saline in the same way. The model group A mice were used for clinical, survival and autopsy observation tests; On the 3rd, 5th and 7th day after inoculation, 5 mice in model group B were dissected randomly for tissue bacterial load and pathological examination (2 mice were dissected at each time point in the control group). The tissue bacterial load of mice was detected by live bacteria plate counting method, and the histopathological changes of mouse tongue, stomach, liver and kidney were observed under light microscope.

　　Results: On the third day after inoculation, the mice in the model group showed obvious white spots on the tongue surface and died with time. The death rate of the mice on the fifth day was more than 50%, and the death rate on the seventh day was 100%. C. albicans could be isolated from the tongue (87.5%), stomach (87.5%), and visceral tissue liver (54.5%), kidney (50.5%), lung (20%), and heart (4%). The proliferation of mycelia was observed under microscope in the tongue, esophagus, stomach, liver, and kidney, There was no growth of C. albicans in the control group, suggesting that the model group mice were infected with C. albicans mucosa, causing a disseminated systemic infection in mice.

　　Conclusion: C Albicans can break through the mucosal immune barrier and cause opportunistic systemic infection in mice under certain conditions, thus aggravating the death of infection.