A型产气荚膜梭菌小鼠感染模型的建立

Establishment of an Mouse Model for Studying Clostridium perfringens Type A Infection

近年来,我国许多牛场暴发产气荚膜梭菌病,同时产气荚膜梭菌病疫苗及其致病机制的研究不断深入。本试验以牛源A型产气荚膜梭菌强毒株C987株为基础,通过灌胃或皮下注射方式接种小鼠,记录其发病和死亡情况,并剖检观察小鼠内脏各器官病变及组织学变化,建立小鼠感染模型。结果表明,灌胃和皮下注射接种方式,A型产气荚膜梭菌对小鼠的半数致死量分别为4.35×109 CFU和8.0×106 CFU。感染小鼠腹部明显膨大,剖检内脏器官均出现明显病变,组织化学染色显示内脏器官大多出现淋巴细胞浸润及不同组织学变化。皮下注射方式在接种细菌数量、试验平行性、小鼠死亡率上均优于灌胃接种方式,因此皮下注射接种方式更适合作为A型产气荚膜梭菌小鼠感染模型的接种途径。本试验为牛A型产气荚膜梭菌疫苗的评价及其致病机制的研究提供了一种合适的动物模型。

In recent years, Clostridium perfringens disease occurred in many of our cattle. At the same time, the researches of Clostridium perfringens disease vaccine and its pathogenic mechanism continued to grow in depth. This study was based on a virulent strain of bovine A type Clostridium perfringens C987 strains,which was inoculated into mice via gavage or subcutaneous injection, We recorded their morbidity and mortality, dissected them and observed mouse visceral organ involvement in histological changes and tried to establish a mouse infection model. The result shows that Median lethal dose of Clostridium per- fringens type A on mouse was 4.35 ×10^9 CFU and 8 ×10^6 CFU in intragastric inoculation method and sub- cutaneous inoculation method. Infected mouse was abdominal markedly swollen and visceral organs showed obvious lesions in necropsy. It revealed that most organs had lymphocyte infiltration and different histolog- ical changes by histochemica[ staining. The subcutaneous injection method is better than the intragastrie inoculation method in bacterial number, test parallelism and the mortality of mice. Therefore, the subcu- taneous inoculation method is a more suitable route of inoculation in the mouse model of Clostridium per- fringens type A infection than the former. The research provides a suitable animal model for bovine source of Clostridium perfringens type A vaccine evaluation and pathogenic mechanism.