Ren Tao, Liang Yong-jie, Cai Ying-yun, Li Chuan-you, Mei Jian, Yuan Zheng-hong, Tao Meng-fei, Tian Miao, Zhao Bing
Department of Respiratory Medicine, East Hospital, Tongji University, Shanghai 200120, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2008 Jan;31(1):46-50.
To investigate the possible mechanisms of mycobacterial clearance induced by CpG-oligodeoxynucleotides (CpG-ODN) in mice.
Eight-week-old female BALB/c mice were treated with intraperitoneal CpG-ODN (30 microg), while the control mice with normal saline. After 2 weeks, the control mice and the CpG-treated mice were infected with Mycobacterium tuberculosis (1 x 10(6) colony-forming units, H(37)Rv strain) through the tail vein. At 3 weeks, 4 weeks and 6 weeks after mycobacterial infection, the lung and the spleen tissues were examined for histopathological changes. Real time-PCR was performed to measure the messenger RNA (mRNA) of interleukin (IL)-12, IL-18, interferon (IFN)-gamma, IL-4, IL-10 and inducible nitric oxide synthase (iNOS) in the tissues. The homogenates of lungs and spleens were cultured, and the colonies were counted after a 4 weeks incubation period at 37 degrees C.
At 3 weeks and 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice showed less mycobacterial burden in the lungs and the spleens than that in the control mice [(0 +/- 0) x 10(6) CFU/g vs (32 +/- 11) x 10(6) CFU/g, (0 +/- 0) x 10(6) CFU/g vs (10 +/- 4) x 10(6) CFU/g; (26 +/- 4) x 10(6) CFU/g vs (56 +/- 8) x 10(6) CFU/g, (4 +/- 3) x 10(6) CFU/g vs (27 +/- 8) x 10(6) CFU/g]. At 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(3.6 +/- 0.5, 1.6 +/- 1.1, 0.32 +/- 0.14) vs (0.20 +/- 0.10, 23.17 +/- 4.72, 16.18 +/- 5.09)], and decreased level of IL-12p40 mRNA (5.66 +/- 0.64 vs 14.54 +/- 1.89), but there was no difference in the levels of IL-4 mRNA and IL-10 mRNA in the lungs between CpG-ODN-pretreated mice and the control mice [(0.30 +/- 0.09 vs 0.26 +/- 0.05), (0.28 +/- 0.05 vs 0.29 +/- 0.08)]. CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(5.54 +/- 1.29 vs 0.79 +/- 0.36), (0.52 +/- 0.07 vs 0.21 +/- 0.06), (9.07 +/- 1.81 vs 5.97 +/- 1.44)], and decreased levels of IL-12p40 mRNA, IL-4 mRNA and IL-10 mRNA [(2.10 +/- 0.27 vs 5.07 +/- 0.39), (0.23 +/- 0.10 vs 1.21 +/- 0.26), (0.10 +/- 0.04 vs 0.57 +/- 0.13)] in the spleens as compared with the control mice. In CpG-ODN-pretreated mice, expression level of IFN-gamma mRNA in the lungs at 6 weeks post-infection was higher than that at 4 weeks post-infection (0.95 +/- 0.27 vs 0.32 +/- 0.14).
The activation of Toll-like receptor-9 (TLR-9) with CpG-ODN could enhance murine mycobacterial clearance in vivo. TLR-9-induced anti-mycobacterial activity involves increased expression of IL-18, IFN-gamma, and iNOS but decreased expression of IL-4 and IL-10.
探讨CpG-寡脱氧核苷酸（CpG-ODN）诱导小鼠清除分枝杆菌的可能机制。
8周龄雌性BALB/c小鼠腹腔注射CpG-ODN（30微克），对照小鼠注射生理盐水。2周后，对照小鼠和经CpG处理的小鼠通过尾静脉感染结核分枝杆菌（1×10⁶菌落形成单位，H37Rv菌株）。在分枝杆菌感染后3周、4周和6周，检查肺和脾组织的组织病理学变化。采用实时聚合酶链反应（Real time-PCR）检测组织中白细胞介素（IL）-12、IL-18、干扰素（IFN）-γ、IL-4、IL-10和诱导型一氧化氮合酶（iNOS）的信使核糖核酸（mRNA）。培养肺和脾的匀浆，在37℃孵育4周后计数菌落。
在分枝杆菌感染3周和4周时，经CpG-ODN预处理的小鼠肺和脾中的分枝杆菌负荷低于对照小鼠[（0±0）×10⁶CFU/g对（32±11）×10⁶CFU/g，（0±0）×10⁶CFU/g对（10±4）×10⁶CFU/g；（26±4）×10⁶CFU/g对（56±8）×10⁶CFU/g，（4±3）×10⁶CFU/g对（27±8）×10⁶CFU/g]。在分枝杆菌感染4周时，经CpG-ODN预处理的小鼠肺中IL-18 mRNA、IFN-γ mRNA、iNOS mRNA水平升高[（3.6±0.5，1.6±1.1，0.32±0.14）对（0.20±0.10，23.17±4.72，16.18±5.09）]，而IL-12p40 mRNA水平降低（5.66±0.64对14.54±1.89），但经CpG-ODN预处理的小鼠与对照小鼠肺中IL-4 mRNA和IL-10 mRNA水平无差异[（0.30±0.09对0.26±0.05），（0.28±0.05对0.29±0.08）]。与对照小鼠相比，经CpG-ODN预处理的小鼠脾中IL-18 mRNA、IFN-γ mRNA、iNOS mRNA水平升高[（5.54±1.29对0.79±0.36），（0.52±0.07对0.21±0.06），（9.07±1.81对5.97±1.44）]，而IL-12p40 mRNA、IL-4 mRNA和IL-10 mRNA水平降低[（2.10±0.27对5.07±0.39），（0.23±0.10对1.21±0.26），（0.10±0.04对0.
