小鼠金黄色葡萄球菌颅内感染模型的建立

Construction of mouse intracranial infection model induced by S.aureus

目的：建立金黄色葡萄球菌颅内感染小鼠模型。方法6～8周龄雌性C57BL/6J小鼠随机分为实验组和对照组,各52只。实验组小鼠颅内注射金黄色葡萄球菌8325-4菌液5μl （5×10^6 CFU）,对照组注射等量无菌生理盐水。造模后观察小鼠症状,最早出现死亡的时间点及48 h存活率；检测肛温、外周血白细胞计数及中性粒细胞百分比；取脑组织做病理切片,观察脑组织病理学改变。结果造模后,实验组小鼠出现反应迟钝、抽搐等症状,12 h开始出现死亡,48 h存活率为26.9%。中性粒细胞百分比明显增高,脑组织病理学检查显示感染处大量中性粒细胞浸润。对照组均未见症状和死亡,脑组织病理学检查正常。结论本组建立的小鼠金黄色葡萄球菌颅内感染模型特征稳定,可用于临床金黄色葡萄球菌颅内感染致病机制的研究。

Objective To construct the mouse intracranial infection model induced by S.aureus. Methods One hundred and six female C57BL/6J mice （6 to 8 weeks old） were equally and randomly divided into experimental and control groups. S.aureus 8325-4 solution 5 μl （5×10^6 CFU） were injected into the brain of the mouse in experimental group, while sterile saline were injected into those of control group. After injection, clinical manifestations, the earliest time point of death and 48-h survival rate were recorded, rectal temperature and hemogram were monitored, and the brain tissues from the pathological section were observed for pathological study. Results After injection, the rats showed symptoms such as slow response and spasm, the earliest time point of death was 12 h, and the 48-h survival rate was 26.9% in the experimental group. Compared with control group, the percentage of neutrophil increased significantly, and the neutrophil granulocyte infiltration in the infection area of brain tissues was observed in experimental group. While there were no symptoms and dead rats in control group, and the brain tissue was normal based on pathological examination. Conclusion The mouse intracranial infection model induced by S.aureus is stable, and can be used in clinical study for pathogenic mechanismof intracranial infection induced by S.aureus.