摘要目的 观察烟草烟雾暴露大鼠外周血与BALF中CD+4白细胞介素(IL)-17+T细胞(Th17细胞)与CD; Foxp3+调节性T细胞(Treg细胞)及相关因子的水平变化,探讨Th17和Treg细胞在烟草诱导气道炎症和COPD的发生与发展中的作用.方法 将40只健康清洁级雄性Wistar大鼠分为暴露12周组和24周组、对照12周组和24周组,每组10只.用烟熏法复制大鼠气道炎症的动物模型.收集BALF进行细胞学计数和分类,采用酶联免疫吸附法检测大鼠血清和BALF上清液中IL-17和IL-6水平,用流式细胞术检测Th17和Treg细胞比例,用实时荧光定量PCR法检测IL-17和Foxp3 mRNA的表达.多组间比较采用单因素方差分析,组内两两比较采用SNK法和GamesHowell法.结果 暴露12周组和24周组大鼠外周血IL-17浓度分别为(52.6±1.8) ng/L和(75.4±6.0) ng/L,BALF中IL-17浓度分别为(78.1 ±5.8) ng/L和(95.0±6.8)ng/L,均显著高于对照12周组[(40.0±3.2) ng/L和(54.5±4.6) ng/L]及24周组[(36.7±3.2) ng/L和(53.9±3.7) ng/L],暴露24周组与其他3组比较,差异均有统计学意义(均P＜0.05).暴露24周组大鼠外周血中IL-6浓度为(31.4±2.1)ng/L,显著高于对照24周组[(11.5±0.5)ng/L]；暴露12周组和24周组大鼠BALF中IL-6浓度分别为(33.3 ±2.3)ng/L和(44.6±3.0)ng/L,显著高于对照12周组和24周组[(15.6±1.8)ng/L和(18.0±1.9) ng/L].暴露12周组和24周组大鼠外周血中Th17细胞比例分别为(1.81±0.19)％和(3.74±0.55)％,BALF中Th17细胞比例分别为(7.84±0.28)％和(8.01±0.39)％,均显著高于对照12周组[(0.97±0.08)％和(5.64±0.54)％]及24周组[(1.08±0.10)％和(5.95±0.48)％],暴露24周组与其他3组比较,差异均有统计学意义(均P＜0.05).暴露12周组和24周组大鼠BALF中Treg细胞比例分别为(8.81±0.49)％和(11.98±0.72)％,均显著高于对照12周组和24周组[(4.34±0.28)％和(5.21±0.42)％].暴露12周组和24周组大鼠外周血中IL-17 mRNA表达量分别为25.7±2.0和33.9±1.5,BALF中IL-17 mRNA表达量分别为22.2±1.8和34.7±4.2,均显著高于对照12周组(11.3±2.6和11.6 ±2.4)及24周组(11.1±2.0和13.5±3.4)；暴露12周组和24周组大鼠BALF中Foxp3 mRNA表达量分别为24.4±2.7和30.3±2.7,显著高于对照12周组和24周组(12.7±2.7和14.6±3.8).暴露组大鼠BALF中Th17细胞与其BALF中细胞总数和巨噬细胞数呈正相关(r值分别为0.512和0.543,均P＜0.05).结论 烟草暴露可导致大鼠气道炎症模型的Th17细胞和Treg细胞及相关炎症因子水平升高,提示Treg细胞可能参与气道炎症的免疫调节,Th17细胞异常升高可能与大鼠气道炎症反应的发生及持续进展有关.

abstractsObjective To evaluate the changes of CD+4 IL-17 + T ( Th17 ) and CD+4 Foxp3 +regulatory T (Treg) cells in peripheral blood and bronchoalveolar lavage fluid (BALF),and therefore to explore the role of Th17 and Treg in cigarette smoke-induced airway inflammation/COPD in rats.Methods Forty male Wistar rats were randomly divided into 4 groups: a 12 wk smoke-exposure group,a 24 wk smokeexposure group,a 12 wk control group and a 24 wk control group (n =10 each). Cells in BALF were collected and analyzed by absolute and differential cell counts.IL-17 and IL-6 levels in serum and BALF were tested by emzyme linked immunosorbent assay (ELISA).The proportion of CD4+ IL-17 + T and CD4+Foxp3 + Treg in peripheral blood and BALF were determined by flow cytometry.The mRNA expressions of IL-17 and Foxp3 were measured by real-time PCR.Comparisons of the data between different groups were performed using one-way ANOVA,and SNK and Games-Howell test were used for comparison between 2 groups.Results Levels of IL-17 were remarkable increased in the 12 wk smoke-exposure group and the 24 wk smoke-exposure group in serum [ (52.6 ± 1.8) ng/L,(75.4 ± 6.0) ng/L] and BALF [ (78.1 ±5.8) ng/L,(95.0 ±6.8) ng/L] compared with the 12 wk control group [ (40.0 ± 3.2) ng/L,(54.5 ±4.6) ng/L] and the 24 wk control group [ (36.7 ±3.2) ng/L,(53.9 ±3.7) ng/L],all P ＜0.05.IL-6in serum was significantly increased in the 24 wk smoke-exposure group [ (31.4 ± 2.1 ) ng/L] compared with the 24 wk control group [ (11.5 ± 0.5) ng/L],and it was increased in the 12 wk and the 24 wk smoke-exposure group [ (33.3 ±2.3) ng/L,(44.6 ±3.0) ng/L] compared with the 12 wk and the 24 wk control group [ ( 15.6 ± 1.8) ng/L,( 18.0 ± 1.9) ng/L] in BALF.Ratio of Th17 was higher in the 12 wk and the 24 wk smoke-exposure groups in peripheral blood [ ( 1.81 ± 0.19 ) ％,( 3.74 ± 0.55 ) ％ ] and BALF [(7.84±0.28)％,(8.01 ±0.39)％] compared with the12 wk [(0.97 ±0.08)％,(5.64 ±0.54 ) ％ ] and the 24 wk control group [ ( 1.08 ± 0.10) ％,(5.95 ± 0.48 ) ％ ].Ratio of Treg in BALF was higher in the smoke-exposure groups [ (8.81 ± 0.49) ％,( 11.98 ± 0.72) ％ ] compared with the control groups [ (4.34 ±0.28)％,(5.21 ±0.42)％ ].The level of IL-17 mRNA was increased in the 12 wk and the 24 wk smoke-exposure group in peripheral blood (25.7 ±2.0,33.9 ± 1.5) and in BALF (22.2 ± 1.8,34.7 ±4.2) compared with the 12 wk ( 11.3 ±2.6,11.6 ±2.4) and the 24 wk ( 11.1 ±2.0,13.5 ±3.4)control groups. Foxp3 mRNA was increased in the smoke-exposure groups (24.4 ± 2.7,30.3 ± 2.7 )compared with the control groups ( 12.7 ± 2.7,14.6 ± 3.8).Th17 in smoke-exposure groups was positively correlated with counts of total cells and macrophages ( r =0.512,0.543,all P ＜ 0.05 ).Conclusions An elevated expression of Th17 and Treg cells and an increase of inflammatory cytokines were evident in airway inflammation of cigarette smoke-exposed rats,suggesting that Treg was involved in the immunological regulation and Th17 was associated with the persistent inflammation in cigarette smoke-induced airway inflammation in rats.