小鼠气性坏疽动物模型的建立

Development of a mouse model of Clostridium perfringens type-A gas gangrene

目的建立产气荚膜梭菌感染小鼠的后肢的气性坏疽动物模型,为早期诊断、了解气性坏疽的致病机理及治疗方法提供依据。方法小鼠随机分成4组,每组10只。三个实验组分别肌肉注射3.5×109、3.5×108和3.5×107cfu/ml浓度的产气荚膜梭菌(ATCC13124)菌液0.1ml,空白对照组肌肉注射生理盐水0.1ml,72h后观察小鼠感染情况,取伤口分泌物作革兰氏染色涂片,细菌血平板厌氧培养和荧光定量PCR方法定量检测。结果 3.5×109、3.5×108、3.5×107cfu/ml实验组和对照组在肌肉注射72h内的死亡率为90%、70%、10%和0%。各组平均存活时间依次为(20:43±11:12)h、(37:24±25:39)h、(68:36±10:45)h和(72:00±0:00)h,死亡小鼠出现了气性坏疽的症状,分泌物培养和镜检出产气荚膜梭菌;未死亡小鼠康复;空白对照组无任何症状。各组Ct值均值为21.21±2.69、28.45±2.74、32.49±2.87和0.00±0.00,组间P值均<0.05。结论成功建立了不同浓度的产气荚膜梭菌在不同时间段内感染小鼠的后肢气性坏疽的动物模型,为了解气性坏疽的致病机理及治疗方法奠定基础。

Objective To develop a mouse model for the study of pathogenesis and treatment of Clostridium perfringens.Methods Four groups of mice were intramuscularly injected with 3.5×109 cfu/ml,3.5×108 cfu/ml,or 3.5×107 cfu/ml of Clostridium perfringens diluted with normal saline,and the control group was injected with 0.1 ml of 9% sodium chloride.The infection situation was evaluated after 72 h.Bacterial smear,bacterial culture and real-time PCR were performed.Results The death rate（and the mean survival time） of mice injected with 3.5×109,3.5×108,3.5×107 cfu/ml and the blank groups were 90%（20：43±11：12） h,70%（37：24±25：39） h,10%（68：36±10：45） h and 0%（72 h）,respectively.All death mice had the symptoms of gas gangrene,and Clostridium perfringens were isolated from the dead mice.In the real-time PCR,the mean Ct values in these 4 groups of mice were 21.21±2.69,28.45±2.74,32.49±2.87 and 0.00±0.00.The difference between groups was statistically significant（P〈0.05）.Conclusion A model of gas gangrene in mice infected with Clostridium perfringens was established.It can be used to study the pathogenesis and treatment of gas gangrene.