CpG ODN对哮喘小鼠气道炎症及GATA-3的影响

Effect of CpG oligodeoxynucleotides on airway inflammation and transcription factor GATA-3 mRNA expression in asthmatic mice

目的观察CpGODN对支气管哮喘小鼠气道炎症及肺组织GATA-3mRNA表达的影响。方法将40只雌性BALB/C小鼠随机分为4组(每组10只):生理盐水对照组(A组);哮喘组(B组);CpGODN干预组(C组);GpCODN对照组(D组)。以鸡卵白蛋白(OVA)致敏小鼠建立哮喘模型,C组和D组在OVA激发前分别予CpGODN及对照GpCODN腹腔注射。在末次激发后24h收集各组小鼠的支气管肺泡灌洗液行白细胞计数及EOS分类计数,ELISA法检测各组小鼠BALF中IL-4、IL-5及IFN-γ水平,肺组织HE染色观察其病理变化以及用逆转录聚合酶链反应(RT-PCR)方法检测肺组织中GATA-3mRNA的表达。结果各组BALF中白细胞总数、嗜酸性粒细胞百分比、IL-4、IL-5和IFN-γ浓度分别为:A组为(7.46±1.77)×105个/mL、(0.75±0.48)%、(26.9±4.6)pg/mL、(41.7±5.1)pg/mL和(110.4±12.1)pg/mL,B组为(21.68±4.40)×105个/mL、(9.50±1.13)%、(267.6±24.5)pg/mL、(218.2±15.2)pg/mL和(47.9±9.6)pg/mL,C组为(8.98±2.23)×105个/mL、(2.90±0.86)%、(85.9±8.1)pg/mL、(63.0±9.6)pg/mL和(221.0±29.9)pg/mL,D组为(20.41±3.47)×105个/mL、(9.60±1.30)%、(260.7±15.7)pg/mL、(205.1±15.8)pg/mL和(52.2±10.7)pg/mL。B组与A组比较差异有显著性(P<0.01),C组与B组比较差异有显著性(P<0.01),D组与B组比较差异无显著性(P>0.05)。C组小鼠肺组织GATA-3mRNA的表达较B组明显减低,差异有显著性(P<0.01),D组与B组比较差异无显著性(P>0.05)。结论CpGODN可以抑制哮喘小鼠Th2型细胞因子生成,抑制肺部GATA-3mRNA的表达,减轻哮喘气道炎症。

[Objective] To investigate the effect of CpG oligodeoxynucleotides（CpG ODN） on airway inflammation and transcription factor GATA-3 mRNA expression in asthmatic mice.[Methods] Fourty female BALB/C mice were randomly divided into four groups（10 mice in each group）： saline control group（group A）; asthmatic group（group B）; CpG ODN intervention group （group C）; GpC ODN control group（group D）. Mice were sensitized by intraperitoneally injection of OVA/alum on days 0, 7, 14, and 21, and subsequently received nebulized 2% OVA on days 25, 26, 27 and 28. Groups C and D were treated with CpG ODN or GpC ODN（50 μg/mouse） intraperitoneally 24 h before OVA inhalation challenges. All the mice were killed 24 h after the final OVA challenge, bronchoalveolar lavage fluid （BALF）were collected for counting total inflammatory cells and the percentage of eosinophils, IFN-γ, IL-4 and IL-5concentrations in BALF were detected using an enzyme-linked immunosorbent assay, transcription factor GATA-3 mRNA expression in lung tissue was detected by reverse transcription-polymerase chain reaction. [Results] The total inflammatory cells, percentage of eosinophils, concentrations of IL-4, IL-5 and IFN-γ in BALF in each group were as follows： in group A they were （7.46±1.77）×10^5/mL, （0.75±0.48）%, （26.9±4.6）pg/mL, （41.7±5.1）pg/mL, （110.4±12.1）pg/mL respectively; in group B they were （21.68±4.40）×10^5/mL, （9.50±1.13）%, （267.6±24.5）pg/mL, （218.2±15.2）pg/mL, （47.9±9.6）pg/mL respectively; in group C they were （8.98±2.23）×10^5/mL, （2.90±0.86）%, （85.9± 8.1）pg/mL, （63.0±9.6）pg/mL, （221.0±29.9）pg/mL respectively; in group D they were （20.41±3.47）×10^5/mL, （9.60±1.30）%, （260.7± 15.7）pg/mL, （205.1±15.8）pg/mL, （52.2±10.7）pg/mL respectively. Group B was significantly different from group A（P 〈0.01）, group C was significantly different from group B（P 〈0.01）, group D was not significantly different from group C（P 〉0.05）. The GATA-3 mRNA expression was reduced in lung tissue in group C compared with group B, group C was obviously different from group B（P 〈0.01）, but there was no difference between group D and group B（P 〉0.05）.[Conclusions] This study suggests that CpG ODN could inhibit production of Th2 cytokines, down-regulate GATA-3 mRNA expression, and relieve the allergic inflammation of airway in asthmatic mice.