回归热螺旋体试验性感染树鼩的研究  

Experimental infection of tree shrew with relapsing fever Borrelia

作　　者：张静 苏春燕 程美慧 时宇 代解杰[1,2] 刘红旗 ZHANG Jing;SU Chunyan;CHENG Meihui;SHI Yu;DAI Jiejie;LIU Hongqi(Institute of Medical Biology,Chinese Academy of Medical Sciences,Kunming 650118,China;Kunming Medical University,Kunming 650500,China)

机构地区：[1]中国医学科学院医学生物学研究所,昆明650118 [2]昆明医科大学,昆明650500

出　　处：《扬州大学学报（农业与生命科学版）》2020年第2期57-62,共6页Journal of Yangzhou University：Agricultural and Life Science Edition

基　　金：国家自然科学基金资助项目(81571549);中国医学科学院医学与健康科技创新工程协同创新团队项目(2016-I2M-3-026、2017-I2M-2-006)。

摘　　要：经腹腔注射回归热螺旋体感染树鼩后,每日采血计数螺旋体数,记录树鼩临床症状和体温变化;试验后期解剖树鼩取其脏器,进行组织病理分析,探讨回归热螺旋体感染树鼩后引起的变化。结果表明:回归热螺旋体在树鼩体内能有效地增殖,感染后7 d左右会出现第1个菌血症高峰,而后开始下降,感染后12~14 d又形成1个峰,最终形成1个"回归"状增殖曲线;体温与未感染树鼩一样,无明显变化,但死亡前会骤降2~10℃;树鼩感染螺旋体后出现双后肢及尾无力等神经症状;剖检及组织病理学分析发现,螺旋体感染造成树鼩肝脏和脾脏内严重炎症,引起树鼩肝脏和脾脏明显肿大,约为正常树鼩的2倍;回归热螺旋体能有效感染树鼩,形成回归状菌血症,并可引起树鼩神经症状。这一研究提示树鼩可作为研究回归热螺旋体感染和致病机制的动物模型。RF Borrelia was intraperitoneally injected into tree shrews, then the number of spirochetes in the peripheral blood was counted daily. The clinical symptoms and body temperature of tree shrews were recorded. Tree shrews were dissected at the end of the experiment, and their organs were harvested for histopathological analysis. We found that RF Borrelia could effectively proliferate in tree shrews. The first peak of bacteremia appeared at day 7 post injection, and then it started to decline. The second peak occurred on the 12 th to 14 th days, eventually forming a "regressive" proliferation curve. The body temperature of tree shrews did not change significantly during the infection. Like uninfected tree shrews, the body temperatures of some infected animals were generally maintained between 40 ℃ and 42 ℃. However, in other infected animals, their body temperatures dropped sharply by 2 ℃ to 10 ℃ before death. Neurological symptoms were observed in these animals, such as weakness in both hind limbs and the tail. Dissection of the infected tree shrews with symptoms and histopathological analysis showed that RF Borrelia infection resulted in the severe inflammation in liver and spleen, both of which became significantly swollen with double weight of those in normal tree shrew. In conclusion, RF Borrelia can effectively infect tree shrews, result in a recurrent bacteremia, and possibly lead to neurological symptoms. The results indicated that tree shrews may serve as an animal model for studying mechanisms of RF Borrelia infection and pathogenicity.

关 键 词：树鼩 回归热螺旋体 菌血症 神经症状 动物模型 

分 类 号：R377.2[医药卫生—病原生物学]