Winston Jenessa A, Thanissery Rajani, Montgomery Stephanie A, Theriot Casey M
Department of Population Health and Pathobiology, North Carolina State University College of Veterinary Medicine.
Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine.
J Vis Exp. 2016 Dec 10(118):54850. doi: 10.3791/54850.
Clostridium difficile is an anaerobic, gram-positive, spore-forming enteric pathogen that is associated with increasing morbidity and mortality and consequently poses an urgent threat to public health. Recurrence of a C. difficile infection (CDI) after successful treatment with antibiotics is high, occurring in 20-30% of patients, thus necessitating the discovery of novel therapeutics against this pathogen. Current animal models of CDI result in high mortality rates and thus do not approximate the chronic, insidious disease manifestations seen in humans with CDI. To evaluate therapeutics against C. difficile, a mouse model approximating human disease utilizing a clinically-relevant strain is needed. This protocol outlines the cefoperazone mouse model of CDI using a clinically-relevant and genetically-tractable strain, R20291. Techniques for clinical disease monitoring, C. difficile bacterial enumeration, toxin cytotoxicity, and histopathological changes throughout CDI in a mouse model are detailed in the protocol. Compared to other mouse models of CDI, this model is not uniformly lethal at the dose administered, allowing for the observation of a prolonged clinical course of infection concordant with the human disease. Therefore, this cefoperazone mouse model of CDI proves a valuable experimental platform to assess the effects of novel therapeutics on the amelioration of clinical disease and on the restoration of colonization resistance against C. difficile.
艰难梭菌是一种厌氧、革兰氏阳性、产芽孢的肠道病原体,其发病率和死亡率不断上升,因此对公共卫生构成了紧迫威胁。抗生素成功治疗后艰难梭菌感染(CDI)的复发率很高,在20%-30%的患者中出现,因此需要发现针对这种病原体的新型疗法。目前的CDI动物模型死亡率很高,因此无法模拟人类CDI中出现的慢性、隐匿性疾病表现。为了评估针对艰难梭菌的疗法,需要一种利用临床相关菌株模拟人类疾病的小鼠模型。本方案概述了使用临床相关且基因易处理的菌株R20291的CDI头孢哌酮小鼠模型。该方案详细介绍了小鼠模型中整个CDI过程中的临床疾病监测、艰难梭菌细菌计数、毒素细胞毒性和组织病理学变化的技术。与其他CDI小鼠模型相比,该模型在给药剂量下并非一致致死,从而能够观察到与人类疾病一致的延长的感染临床过程。因此,这种CDI头孢哌酮小鼠模型证明是一个有价值的实验平台,可用于评估新型疗法对改善临床疾病以及恢复对艰难梭菌的定植抗性的效果。