Li You-lun, Chen Bao-wen, Xu Miao, Luo Yong-ai, Wang Guo-zhi, Shen Xiao-bing, Su Cheng
Department of Respiratory Medicine, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2010 Sep;33(9):684-7.
To establish the guinea pig model of latent Mycobacterium tuberculosis (MTB) H₃₇Rv infection, and to study the multiplication dynamics of MTB in vivo, and the relationship between latent MTB infection and PPD skin test.
Sixty-two guinea pigs were randomly divided into the model group (n = 42) and the control group (n = 20), and the model group was subdivided into a 4 weeks group (n = 12), an 8 weeks group (n = 21) and a 12 weeks group (n = 9), challenged by 500 CFU H₃₇Rv with restored toxicity. After 2 weeks challenge, the model groups were treated with isoniazid (INH, 10 mg/kg) + pyrazinamidum aldinamide (PZA, 40 mg/kg) for 4 weeks, 8 weeks and 12 weeks respectively. The natural recurrence of tuberculosis was observed in the model 4 weeks group, and the natural and induced recurrence by dexamethasone was observed in the model 8 weeks group and 12 weeks group. PPD skin test, the pathologic changes, and MTB quantity of organs were observed.
In the control group, the average MTB quantity of spleen was 3.3 lg CFU after 2 weeks challenge, and the average MTB quantity of spleen and lung in guinea pigs were 4.5 lg CFU and 1.8 lg CFU respectively after 6 weeks challenge, and they reached 5.3 lg CFU and 5.4 lg CFU at 18 weeks respectively. The latent MTB infection of the model 4 weeks group recurred naturally 12 weeks after stopping treatment. The latent MTB infection of the model 8 weeks group recurred naturally and by dexamethasone treatment. The latent MTB infection of the model 12 weeks group did not recur naturally, but dexamethasone induced recurrence. The positive PPD response correlated with recurrence.
A latent MTB infection model was established successfully by H₃₇Rv challenge and treatment with INH and PZA. The latent MTB infection may recur naturally or by induction. The PPD response was related to tuberculosis recurrence.
建立豚鼠结核分枝杆菌（MTB）H₃₇Rv潜伏感染模型，研究MTB在体内的增殖动力学以及潜伏MTB感染与PPD皮肤试验之间的关系。
将62只豚鼠随机分为模型组（n = 42）和对照组（n = 20），模型组再分为4周组（n = 12）、8周组（n = 21）和12周组（n = 9），用500 CFU具有恢复毒性的H₃₇Rv进行攻击。攻击2周后，模型组分别用异烟肼（INH，10 mg/kg）+吡嗪酰胺（PZA，40 mg/kg）治疗4周、8周和12周。观察模型4周组结核病的自然复发情况，观察模型8周组和12周组结核病的自然复发及地塞米松诱导复发情况。观察PPD皮肤试验、病理变化及各器官MTB数量。
对照组攻击2周后脾脏MTB平均数量为3.3 lg CFU，攻击6周后豚鼠脾脏和肺脏MTB平均数量分别为4.5 lg CFU和1.8 lg CFU，18周时分别达到5.3 lg CFU和5.4 lg CFU。模型4周组潜伏MTB感染在停药12周后自然复发。模型8周组潜伏MTB感染自然复发并经地塞米松治疗后复发。模型12周组潜伏MTB感染未自然复发，但地塞米松诱导复发。PPD阳性反应与复发相关。
通过H₃₇Rv攻击及INH和PZA治疗成功建立了潜伏MTB感染模型。潜伏MTB感染可能自然复发或诱导复发。PPD反应与结核病复发有关。
