慢性阻塞性肺疾病大鼠肺树突细胞数量及成熟度变化与慢性炎症的关系

目的 观察香烟烟雾暴露对大鼠肺组织树突细胞数量、成熟度及肺组织慢性炎症变化的影响.方法 将30只雄性F344大鼠按随机数字表法分为香烟烟雾暴露组(暴露组)、断烟组和健康对照组(对照组),每组10只.采用香烟烟雾暴露法建立大鼠COPD模型,HE染色法检测大鼠气道炎症病理评分及肺泡平均内衬间隔,免疫组织化学ABC法观察大鼠肺组织中CD11c+、CD86+和CD8+ T细胞的分布及数量变化,流式细胞术检测CD11c+/CD86+和CD11c+/主要组织相容性复合体(MHC)Ⅱ+与CD11c+树突细胞比值.结果 暴露组和断烟组大鼠肺组织中出现COPD特征性病理改变,气道炎症病理评分(390±33)分和(324±28)分]及肺泡平均内衬间隔(68±11)μm和(58±9)μm]明显高于对照组(56±13)分和(36±6)μm],差异均有统计学意义(F值分别为459.85和34.03,均P＜0.05).暴露组和断烟组大鼠CD11c+树突细胞阳性率(1.47±0.12)%和(1.30±0.17)%]及CD86+树突细胞阳性率(1.26±0.18)%和(1.02±0.08)%]均明显高于对照组(0.96±0.08)%和(0.65±0.03)%],差异均有统计学意义(F值分别为6.55和30.26,均P＜0.05);暴露组和断烟组大鼠CD8+T细胞阳性率(2.72±0.15)%和(2.35±0.23)%]均明显高于对照组(1.39±0.11)%],差异有统计学意义(F=16.07,P＜0.05);暴露组和断烟组大鼠CD11c+/CD86+树突细胞及CD11c+/MHCⅡ+树突细胞占CD11c+树突细胞比例(5.5±0.4)%和(4.8±0.4)%]及(4.2±0.3)%和(3.3±0.3)%]明显低于对照组(8.0±0.5)%和(6.1±0.5)%],差异均有统计学意义(F值分别为14.34和12.82,均P＜0.05).暴露组与断烟组上述各项指标比较,差异均无统计学意义(t值为1.10～2.11,均P＞0.05).结论 香烟烟雾暴露诱导COPD大鼠肺组织中树突细胞数量明显增加,成熟度明显下降,断烟后此趋势无明显变化,且以CD8+ T细胞浸润为主的慢性炎症反应持续存在,提示树突细胞数量变化及成熟异常可能参与了COPD慢性炎症迁延进展.

Abstract：

Objective To evaluate the changes in the number and maturation of lung tissue dendritic cells (DCs) and to assess the chronic inflammation in a cigarette smoke-induced COPD model in rats.Methods Thirty male F344 rats were randomly divided into 3 groups (n = 10):a control group, a smoke-exposure group and a smoking cessation group.Rat lung pathomorphological changes were observed by hematoxylin-eosin (HE) stain.Lung tissue CD11c+ DCs, CD85+ DCs and CD8+ T cell numbers were observed by immunohistochemisty method.Flow cytometry was used for detection of CD11c+/CD86+ DCs and CD11c+/MHCⅡ + DCs proportions.Results The airway inflammatory pathological score and the mean linear intercept (MLI) obtained from he smoke-exposure group and the smoking cessation group (390 ± 33,324 + 28 ) and(68 ± 11 ) μm, (58 ± 9) μm]were higher than those in the control group ( 56 ± 13 ) and ( 36 ± 6 ) μm( F =459.85 and 34.03, all P ＜0.05 ).In the smoke-exposure group and the smoking cessation group, the positive rate of CD11c+ DCs(1.47 ±0.12)%, (1.30 ±0.17)%], and the positive rate of CD86+ DCs ( 1.26 ± 0.18 ) %, ( 1.02 ± 0.08 ) %]were higher than those in the control group( 0.96 ± 0.08 ) %,(0.65 ± 0.03 ) %]( F = 6.55 and 30.26, all P ＜ 0.05 ), but there was no significant difference between the smoke-exposure group and the smoking cessation group ( t = 1.10 and 1.47, all P ＞ 0.05 ).In the smoke-exposure group and the smoking cessation group, CD8+ T positive rate(2.72 ±0.15)%, (2.35 ±0.23)%]was higher than that in the control group(1.39 ±0.11)%](F = 16.07, P ＜0.05).CD11c+/CD86+ DCs and CD11c+/MHC Ⅱ+DCs percentages(5.5 ±0.4)%, (4.8 ±0.4)%],(4.2 ±0.4)%, (3.3±0.3 )%]decreased in the smoke-exposure group and the smoking cessation group as compared to the control group(8.0±0.5 ) %, (6.1 ± 0.5 ) %]( F = 14.34 and 12.82, all P ＜ 0.05 ).There was no significant difference between all the above index from the smoke-exposure group and the smoking cessation group ( t = 1.10 and 2.11, all P ＞ 0.05 ).Conclusions Cigarette smoke exposure induced increased DCs transmigrated and influenced the maturation of DCs in COPD rats.Even after smoking cessation, non-specific chronic inflammation was still present, suggesting that DCs number and maturation abnormality may be involved in the chronic inflammation of COPD.

The association of non-specific chronic inflammation with dendritic cells in a rat model of chronic obstructive puhnonary disease

Objective To evaluate the changes in the number and maturation of lung tissue dendritic cells (DCs) and to assess the chronic inflammation in a cigarette smoke-induced COPD model in rats.Methods Thirty male F344 rats were randomly divided into 3 groups (n = 10):a control group, a smoke-exposure group and a smoking cessation group.Rat lung pathomorphological changes were observed by hematoxylin-eosin (HE) stain.Lung tissue CD11c+ DCs, CD85+ DCs and CD8+ T cell numbers were observed by immunohistochemisty method.Flow cytometry was used for detection of CD11c+/CD86+ DCs and CD11c+/MHCⅡ + DCs proportions.Results The airway inflammatory pathological score and the mean linear intercept (MLI) obtained from he smoke-exposure group and the smoking cessation group (390 ± 33,324 + 28 ) and(68 ± 11 ) μm, (58 ± 9) μm]were higher than those in the control group ( 56 ± 13 ) and ( 36 ± 6 ) μm( F =459.85 and 34.03, all P ＜0.05 ).In the smoke-exposure group and the smoking cessation group, the positive rate of CD11c+ DCs(1.47 ±0.12)%, (1.30 ±0.17)%], and the positive rate of CD86+ DCs ( 1.26 ± 0.18 ) %, ( 1.02 ± 0.08 ) %]were higher than those in the control group( 0.96 ± 0.08 ) %,(0.65 ± 0.03 ) %]( F = 6.55 and 30.26, all P ＜ 0.05 ), but there was no significant difference between the smoke-exposure group and the smoking cessation group ( t = 1.10 and 1.47, all P ＞ 0.05 ).In the smoke-exposure group and the smoking cessation group, CD8+ T positive rate(2.72 ±0.15)%, (2.35 ±0.23)%]was higher than that in the control group(1.39 ±0.11)%](F = 16.07, P ＜0.05).CD11c+/CD86+ DCs and CD11c+/MHC Ⅱ+DCs percentages(5.5 ±0.4)%, (4.8 ±0.4)%],(4.2 ±0.4)%, (3.3±0.3 )%]decreased in the smoke-exposure group and the smoking cessation group as compared to the control group(8.0±0.5 ) %, (6.1 ± 0.5 ) %]( F = 14.34 and 12.82, all P ＜ 0.05 ).There was no significant difference between all the above index from the smoke-exposure group and the smoking cessation group ( t = 1.10 and 2.11, all P ＞ 0.05 ).Conclusions Cigarette smoke exposure induced increased DCs transmigrated and influenced the maturation of DCs in COPD rats.Even after smoking cessation, non-specific chronic inflammation was still present, suggesting that DCs number and maturation abnormality may be involved in the chronic inflammation of COPD.