中国恒河猴结核病模型的建立与评价

Establishment and evaluation of a Chinese rhesus model of tuberculosis

目的探讨中国恒河猴结核病模型的建立方法，并对中国恒河猴作为结核病动物模型做出评价。方法应用简单随机分组法将12只中国恒河猴分为注入低菌量组（20CFU）、注入高菌量组（100CFU）和滴注高菌量组（100CFU），每组4只，雌雄各半。将MTB分别通过支气管镜和气管内滴注法感染猴，动态观察恒河猴的临床表现，定期进行ESR、C反应蛋白、PPD试验和x线胸片检查，感染后24周行病理检查。采用方差分析进行多组间比较。结果3组感染MTB的恒河猴均出现不同程度的体温升高、体重下降、食欲下降和咳嗽等症状，体温于感染后8周达到高峰[（40．1±0．2）℃]，感染后24周体重下降明显[（-5．5±5．6）％]，感染后6～8周ESR明显升高[（36±40）mm／1h]，感染后6—24周C反应蛋白明显升高[（75．8±49．8）mg／L]，旧结核菌素试验均为阳性。注入低菌量组动物的病变进展缓慢，X线胸片以斑片影为主，注入高菌量组和滴注高菌量组动物的病变发展迅速，4—12周以斑片影和结节影为主，12—24周以片状影和实变影多见。肺组织、纵隔淋巴结、肾脏和脾脏可见与人结核病相似的结核性肉芽肿及干酪样坏死，抗酸染色均为阳性，病理改变严重程度为注入高菌量组〉滴注高菌量组〉注入低菌量组，注入高菌量组右肺细菌载量[（6．7±1．0）lg CFU／g]高于注入低菌量组和滴注高菌量组[（5．9±1．3）lg CFU／g和（5．8±2．0）lg CFU／g]，3组间比较，差异无统计学意义（F=0．97，P〉0．05）。结论中国恒河猴经支气管镜和气管内滴注MTB均可成功建立非人灵长类动物结核病模型，其临床表现、疾病进展及病理改变与人原发性结核病和血行播散性结核病相似。

Objective To establish and evaluate the Chinese rhesus model of tuberculosis. Methods Twelve Chinese rhesus macaques, randomly divided into 3 groups, were inoculated with 2 different doses of Mycobacterium tuberculosis H37Rv strain via both bronchoseopic and intratracheal instillation into the lungs. Clinical observation and laboratory examinations were performed, including erythrocyte sedimentation rate, C-reactive protein, tuberculin skin test and X-ray examination. Histopathological assessments were performed in the 24th week postinfection. Statistical analysis was performed by ANOVA in the 3 groups. Results After infection all the animals manifested fever, weight lose, lack of appetite, coughing and other symptoms of tuberculosis. The temperature gradually increased and reached a peak [ （40. 1 ±0. 2） ℃ ] at the 8th week postinfection. The weight decreased significantly at 24th week postinfection （ - 5.5 ± 5.6） %. Erythroeyte sedimentation rate elevated significantly at the 6th to 8th week postinfeetion （36 ±40） ram/1 h. C-reactive protein was significantly increased at the 6th to 24th week after infection （75.8 ±49. 8） mg/L. The positive rate of tuberculin skin test was 100%. In GroupⅠ （bronehoseopie instillation, 20 CFU ） the disease developed slowly, and the main manifestation of chest X-ray was patchy shadows. In group Ⅱ （bronchoscopic instillation, 100 CFU） and group m （intratracheal instillation, 100 CFU） the disease developed rapidly, and the main manifestation of chest X-ray was patchy and nodular lesions during the 4th to the 12th week postinfection, but became large patchy and consolidation lesions during the 12th to the 24th week postinfection. Tuberculosis granuloma and caseous necrosis, similar to the pathological changes of human tuberculosis, were found in the lungs, mediastinal lymph nodes, kidney and spleen. The results of acid-fast stain were positive. The most serious pathological manifestations were observed in group Ⅱ, followed by group Ⅲ and group I . The highest bacterial load of the right lung was seen in group Ⅱ , followed by group I and group m. Conclusions A chinese rhesus model of tuberculosis was successfully developed via both bronchoscopic and intratracheal instillation. Their clinical manifestations, disease progression and pathological changes were similar to human primary tuberculosis and hematogenous disseminated tuberculosis.