论文部分内容阅读
目的观察CpG寡脱氧核苷酸(ODN)对结核分枝杆菌感染小鼠的保护作用及其机制。方法将96只雌性BALB/c小鼠按随机数字表法分为4组,每组24只,分别为CpGODN免疫组(A组)、对照ODN免疫组(B组)、感染对照组(C组)和正常对照组(D组)。A组和B组小鼠于攻毒前2周腹腔注射CpGODN和对照ODN(30μg/只)。A、B、C3组小鼠经尾静脉注射结核分枝杆菌(H37Rv,1×106条/只)。攻毒后3周,每组处死12只小鼠,观察肺脾组织病理学变化,检测肺脾组织Toll样受体9(TLR9)mRNA、γ干扰素(IFNγ)mRNA、白细胞介素(IL)4mRNA、IL10mRNA和IL6mRNA表达以及肺和脾组织菌落计数。同时观察4组小鼠生存率。结果CpGODN能够提高结核分枝杆菌感染小鼠的生存率。A组[(20.37±1.12)g]小鼠体重高于B组[(17.50±0.62)g]和C组[(17.15±0.97)g,P均<0.01];A组小鼠肺湿重[(0.25±0.02)g]与B组[(0.27±0.34)g,P>0.05]相似,但低于C组[(0.28±0.26)g,P<0.01];A组小鼠脾湿重[(0.63±0.37)g]高于B组[(0.39±0.05)g]和C组[(0.38±0.02)g,P均<0.01]。A组小鼠肺部炎症较B组和C组小鼠为轻。A组小鼠肺脏和脾脏组织匀浆未见结核分枝杆菌菌落生长。A组小鼠肺、脾组织TLR9mRNA表达(分别为0.61±0.29和0.72±0.48)与B组(分别为0.58±0.35和0.64±0.28)和C组(分别为0.60±0.32和0.65±0.31)相似(P>0.05),但高于D组(分别为0.11±0.08和0.26±0.22,P<0.01),CpGODN对TLR9mRNA的表达无影响。A组小鼠肺、脾组织IFNγmRNA表达(分别为0.44±0.07和0.76±0.09)高于B组(分别为0.19±0.05和0.22±0.05)和C组(分别为0.16±0.04和0.18±0.08,P均<0.01)。A组小鼠肺、脾组织IL6mRNA的表达(分别为1.56±0.29和8.21±0.82)高于B组(分别为0.86±0.55和0.16±0.09)和C组(分别为0.78±0.21和0.06±0.04,P均<0.01)。A组小鼠肺、脾组织IL4mRNA的表达(分别为0.18±0.05和0.06±0.02)低于B组(分别为0.31±0.06和1.22±0.01)和C组(0.35±0.04,1.31±0.31,P均<0.01)。A、B、C3组小鼠肺组织IL10mRNA的表达分别为0.28±0.06、0.26±0.04、0.28±0.05,差异无统计学意义(P>0.05);A组脾组织IL10mRNA的表达(0.05±0.02)低于B组(0.57±0.09)和C组(0.65±0.15,P均<0.01)。结论CpGODN可促进Th1型免疫反应,抑制Th2型免疫反应,增强小鼠抵抗结核分枝菌感染的能力。
Objective To observe the protective effect and mechanism of CpG oligodeoxynucleotides (ODN) on Mycobacterium tuberculosis infection in mice. Methods 96 female BALB / c mice were randomly divided into 4 groups (24 mice in each group): CpG ODN immunized group (group A), control ODN immunized group (group B), infected control group (group C) ) And normal control group (D group). Group A and group B mice were intraperitoneally injected with CpG ODN and control ODN (30 μg / mouse) two weeks prior to challenge. A, B, C3 mice were injected via the tail vein of Mycobacterium tuberculosis (H37Rv, 1 × 106 / only). Three weeks after the challenge, 12 mice in each group were sacrificed to observe the histopathological changes of lung and spleen. Toll-like receptor 9 (TLR9) mRNA, interleukin (IFN) mRNA, interleukin (IL) 4 mRNA, IL10 mRNA and IL6 mRNA expression as well as lung and spleen colony counts. Simultaneous observation of 4 groups of mice survival rate. Results CpGODN increased the survival rate of M. tuberculosis infected mice. The weight of mice in group A [(20.37 ± 1.12) g] was significantly higher than that in group B [(17.50 ± 0.62) g] and group C [(17.15 ± 0.97) g, P <0.01] (0.25 ± 0.02) g] was similar to that of group B [(0.27 ± 0.34) g, P> 0.05], but lower than that of group C (0.28 ± 0.26 g, P <0.01) (0.63 ± 0.37) g] were higher than those in group B [(0.39 ± 0.05) g] and group C [(0.38 ± 0.02) g, P <0.01 respectively. Group A mice lung inflammation than Group B and C mice were light. A group of mice lung and spleen homogenate did not see the growth of Mycobacterium tuberculosis. The TLR9 mRNA expression in the lungs and spleens of mice in group A (0.61 ± 0.29 and 0.72 ± 0.48, respectively) was similar to those in group B (0.58 ± 0.35 and 0.64 ± 0.28, respectively) and C (0.60 ± 0.32 and 0.65 ± 0.31, respectively) (P> 0.05), but higher than that in group D (0.11 ± 0.08 and 0.26 ± 0.22 respectively, P <0.01). CpG ODN had no effect on the expression of TLR9 mRNA. The expression of IFNγ mRNA in lung and spleen in group A was significantly higher than those in group B (0.19 ± 0.05 and 0.22 ± 0.05, respectively) (0.44 ± 0.07 and 0.76 ± 0.09, respectively) and group C (0.16 ± 0.04 and 0.18 ± 0.08, P <0.01). The expression of IL6mRNA in lungs and spleens of group A was significantly higher than those in group B (1.56 ± 0.29 and 8.21 ± 0.82, respectively, 0.86 ± 0.55 and 0.16 ± 0.09, respectively) and group C (0.78 ± 0.21 and 0.06 ± 0.04, respectively , P <0.01). The expression of IL4mRNA in lung and spleen of group A was lower than those in group B (0.31 ± 0.06 and 1.22 ± 0.01, respectively) and group C (0.35 ± 0.04, 1.31 ± 0.31, P All <0.01). The expression of IL10mRNA in the lungs of A, B and C3 groups was 0.28 ± 0.06, 0.26 ± 0.04 and 0.28 ± 0.05, respectively (P> 0.05) Lower than that in group B (0.57 ± 0.09) and group C (0.65 ± 0.15, P <0.01). Conclusion CpGODN can promote Th1-type immune response, inhibit Th2-type immune response and enhance the ability of mice to resist Mycobacterium tuberculosis infection.