伯氏考克斯体新桥株感染BALB/c小鼠的实验研究

BALB/c mice experimentally infected with Coxiella burnetii Xinqiao strain

目的:分析伯氏考克斯体新桥株对BALB/c小鼠的感染性。方法:用伯氏考克斯体新桥株腹腔接种感染小鼠,于感染后7,14,21,28 d分别处死小鼠,采用伯氏考克斯体特异的荧光定量PCR检测感染小鼠肝、脾、肺组织样本中伯氏考克斯体含量。采用间接免疫荧光法检测感染小鼠血清特异性抗体水平。结果:感染后28 d内,小鼠肝、脾、肺组织中均检出大量伯氏考克斯体,第7天检出量最高,脾的含量显著高于肝和肺,肝的含量显著高于肺。随着感染时间延长,伯氏考克斯体检出量呈下降趋势,但血清特异性抗体水平则不断升高。结论:伯氏考克斯体新桥株为强毒株,可以引起BALB/c小鼠较长时间的稳定感染;BALB/c小鼠可以用作伯氏考克斯体感染模型。

Objective：To analyze the pathogenicity of Coxiella burnetii Xinqiao strain in BALB/c mice. Methods： BALB/c mice were injected intraperitoneally with C. burnetii Xinqiao strain. The mice were sacrificed on the days 7, 14, 21, 28 after infection,respectively. The liver, spleen, and lung tissues collected from the mice were examined by a realtime quantitative PCR for C. burnetii. Results：A large amount of C. burnetii was found in liver, spleen, and lung tissues and the highest level was detected on day 7 after infection; the amount of C. burnetii in spleen tissues was significantly higher than that in liver or lung tissues. The amount of C. burnetii in tissues was significantly reduced on day 14 after infection. However, the levels of specific antibody （IgG） detected by indirect immunofluorescence assay rose with the infection progress. Conclusion： C. burnetii Xinqiao strain is a virulent strain and may cause severe infection in BALB/c mice, and BALB/c mice may be used as the animal model for evaluation of infection caused by C. burnetii.