ABSTRACT
Objective To establish a mouse model of systemic C. albicans infection by oral inoculation of the pathogen and observe the proliferation and distribution of C. albicans in vivo tissues. Methods Male ICR mice(n=46) were used as the experiment group(n=40) and blank group (n=6). Cotton swabs with C. albicans were used to infect the mice (7 × 106 CFU/mL), and the blank group with saline. The mice of the experiment group were randomly divided into two groups:model group A for clinical assessment (n=20) and model group B for tissue fungal burden detection (n=20). Clinical score, survival and autopsy were carried out among the model group A. Five mice were randomly killed from the model group B at 3 d, 5 d and7 d after infection, respectively ( blank group killed 2 mice each time) . Microbial load tablet method was used to detect the tissue fungal burdens in different tissues, meanwhile samples of tongue, esophagus, stomach, liver, kidney, lung of infected mice were taken for pathological examination. Results White spot appeared on the surface of tongue since 3 d postinfection and increased with time and finally caused death. The mortality reached over 50% at 5 d. C. albicans was not only detected from the tongue (87?5%), stomach (87?5%), liver (54?5%), kidney (50?5%), lung (20%) and heart (4%), but also was microscopically seen mycelia proliferation in the tongue, stomach, liver, and kidney , yet not seen in the control group, showing that C. albicans caused disseminated systemic infection through mucosal infection in mice. Conclusions C. albicans can induce opportunistic systemic infection by breakthrough the mucosal immune barrier, so as to increase the infection to death.
ABSTRACT
Objective To establish and analyze a mouse model of Staphylococcus aureus?induced arthritis ( Staphy?lococcus aureus septic arthritis, SA) , and provide an animal model for arthritis mechanism research and drug development. Methods Mice were immunosuppressed with cyclophosphamide, then intravenously inoculated with Staphylococcus au?reus. The gross characteristics of the joints were observed, the arthritis indexes were analyzed, and the pathological scores of the model mice were evaluated. Results From the first day after bacterial inoculation, the mouse joints were swollen. Pathological examination revealed lesions varying from mild and disarranged joint synovial hyperplasia to synovial thickening and intra?articular invasion, and increased neutrophil infiltration. Conclusions A mouse model of Staphylococcus aureus?induced arthritis is successfully established in this study. This model can be developed in a relatively short time, can not only simulate the clinical symptoms and signs and disease progression of human arthritis, but also to a certain extent reflects the etiology, infection and immunological mechanisms of human arthritis.