经呼吸道感染马尔尼菲青霉菌的动物实验研究

目的对不同来源马尔尼菲青霉菌(penicillium marneffei,PM)的致病力情况进行初步探讨。方法将实验组小鼠分为R组和H组,分别经呼吸道吸入接种分离自广西野生银星竹鼠的PM菌株(竹鼠寄生株)及广西地区马尔尼菲青霉病(peniciliosis marneffei,PSM)患者血液的PM菌株(人感染株)活菌悬液,7天后处死并解剖,肉眼观察肺脏感染情况;取左肺下叶组织行真菌培养并比较阳性率差异;取左肺上叶组织行病理切片观察了解其病理改变;取右肺组织匀浆接种PDA平板培养基25℃培养48h后计数菌落,比较二者肺组织菌载量,同时分析安慰剂组和空白对照组小鼠的情况。结果实验组小鼠(R组和H组)感染PM后发病率100%;两种不同来源的PM感染小鼠后肺脏肉眼观察无明显差异;感染不同来源PM的小鼠肺组织菌载量无差异;不同来源PM感染的小鼠肺脏病理改变无明显差异;安慰剂组小鼠有轻微病理改变;空白对照组小鼠无病理改变。结论两种不同来源的PM菌株经呼吸道吸入感染途径均可引起小鼠肺部致病;竹鼠寄生株PM与人感染株PM对小鼠的致病力无差异。

Animal Experimental Study on the Infection of Penicillium Marneffei Through Respiratory Inhalation

Objective The pathogenicity of Penicillium marneffei isolated from bamboo rats and patients was respectively compared by animal experimental infection through respiratory inhalation.Method Experimental mice were divided into two groups.Group R and group H were inoculated with conidia suspension of wild isolates and clinical isolates respectively through respiratory inhalation.Then the mice were sacrificed after seven days.The infection status of mice lung by visual observation was compared.The left lower lobe infected by Penicillium marneffei were taken to fungal culture and the positive rates were compared.Histopathological changes of the left upper lobe were examinated and compared.The right lung tissues were cultured in PDA plate at 25℃ for 48 hours and the bacterial load were compared and analyzed by counting homogenate colonies.The state of placebo group and the blank control group were analyzed.Results The incidence of mice(Group R and group H)infected by Penicillium marneffei was 100%.The lung damage was not different significantly by visual observation.The bacterial loads of the lung tissue were not different significantly.There was no significant difference on the pathological changes of mice lung tissue between the two groups.The lung tissue of placebo group had slight pathological changes.The lung tissue of blank control group had no pathological changes.Conclusions The two different kinds of Penicillium marneffei are pathogenic on the lung of mice infected through respiratory inhalation.There is no significant difference of pathogenicity between Penicilium marneffei isolated from bamboo rats and patients.