地塞米松对哮喘大鼠Th2细胞分化的影响  

Effects of Dexamethasone on Differentiation of T Helper Ⅱ Type Cells in Rat Asthma Model

作　　者：张华[1,2] 程琳[1,3] 陶晓南[1] 陈菊英[1,4] 

机构地区：[1]华中科技大学同济医学院附属协和医院呼吸内科,武汉430022 [2]胜利油田建翔医院呼吸内科,山东滨州256622 [3]胜利油田滨南医院呼吸内科,山东滨州256600 [4]胜利油田滨南医院病理科,山东滨州256600

出　　处：《中华临床免疫和变态反应杂志》2011年第2期88-91,I0001,共5页Chinese Journal of Allergy & Clinical Immunology

基　　金：湖北省卫生厅科研基金(No.JXIB051)

摘　　要：目的研究糖皮质激素对哮喘大鼠肺组织Th2细胞分化的影响,探讨糖皮质激素治疗哮喘的可能机制。方法 24只SPF(无特定病原体)级SD(远交群)雄性大鼠随机分为3组,用卵清蛋白(OVA)建立哮喘模型:正常对照组、哮喘组、地塞米松组。留取支气管肺泡灌洗液(BALF)进行细胞计数及分类,采取ELISA法测定BALF中白细胞介素4(IL-4)的含量;应用免疫组化及流式细胞术测定肺组织中GATA-3(GATAbindingprotein3)的表达。结果哮喘组BALF中嗜酸性粒细胞占细胞总数百分比(EOS%)、淋巴细胞占细胞总数百分比(Lym%)、IL-4水平,显著高于正常对照组及地塞米松组(P<0.01);免疫组化及流式细胞术显示,哮喘组GATA-3表达显著高于正常组及地塞米松组(P<0.01);地塞米松组BALF中EOS%、Lym%和IL-4水平、肺组织GATA-3阳性表达与正常组比较差异无统计学意义(P>0.05)。结论转录因子GATA-3及细胞因子IL-4的高表达,参与哮喘的病理生理过程;地塞米松可减少肺组织炎性细胞浸润,下调哮喘大鼠GATA-3、IL-4水平,提示其可抑制Th0细胞向Th2细胞分化,使Th1/Th2比例趋于平衡。Objective To investigate the effects of dexamethasone on differentiation of T helper II type cells in rat asthma model,to explore the mechanism of dexamethasone in the treatment of asthma.Methods Twenty-four male SD rats were randomly divided into three groups,which were control group,asthma group and dexamethasone-treatment group.The rat asthma model was challenged by ovalbumin （OVA）.The cells in broncho-alveolar lavage fluid （BALF） were counted and classified.The concentrations of IL-4 in BALF were measured by sandwich enzyme-linked immunosorbent assay.The expression of GATA-3 protein in lung tissue was detected by immunohistochemistry and flow cytometry.Results 1） The percentage of eosinophils of total cell number （EOS%）,the percentage of lymphocyte of total cell number （Lym%） and the concentration of IL-4 in asthma group were significantly higher than that in control group and dexamethasone-treatment group （P 0.01） ;2） The results of immunohistochemistry and flow cytometry showed that the level of GATA-3 expression in lung tissue of asthma group was significantly higher than that in control group and dexamethasone-treatment group （P 0.01）;3） There were no significant difference between percentage of eosinophils of total cell number （EOS%）,the percentage of lymphocyte of total cell number （Lym%）,and IL-4 concentration in BALF and the GATA-3 positive expression in lung tissue in control group and in dexamethasone-treatment group （P 0.05）.Conclusion The high expression of transcription factor GATA-3 and cytokine IL-4 in rat asthma model was involved in the patthogenesis asthma.Dexamethasone can down-regulate the expression of GATA-3 and IL-4,which indicated that it can inhibit the cell differentiation from Th0 to Th2,and regain the Th1/Th2 balance.

关 键 词：哮喘 白细胞介素4 GATA-3 地塞米松 

分 类 号：R562.25[医药卫生—呼吸系统]