大鼠变应性鼻炎模型中T-bet/GATA-3基因表达的研究

Expression of T-bet and GATA-3 Genes in Rat Allergic Rhinitis Models

目的探讨大鼠变应性鼻炎模型中血液单核细胞中T-bet/GATA-3基因表达及在变应性鼻炎发生发展中的作用.方法 20只SD大鼠,雌雄各半,随机分为实验组和对照组,每组各10只.实验组用卵蛋白致敏,以氢氧化铝溶胶和灭活的百日咳杆菌为佐剂,卵蛋白滴鼻建立大鼠变应性鼻炎模型,对照组以氢氧化铝溶胶和灭活的百日咳杆菌生理盐水皮下注射生理盐水滴鼻.在末次激发10 h,心脏采血,分离血浆和单核细胞.用ELISA法检测血浆中IL-4和INF-γ的水平,用RT-PCR法测定单核细胞中T-bet/GATA-3 mRNA的表达,对结果进行统计学分析.结果实验组血浆中IL-4和INF-γ(x±s)的水平分别是(14.241±1.963)和(12.364±2.524)Pg/mL;T-bet mRNA和GATA-3 mRNA(x±s)相对表达量分别为(0.433±0.514)和(1.029±0.690).对照组血浆中IL-4和INF-γ(x±s)的水平分别是(4.916±0.600)和(16.303±5.335)Pg/mL;T-bet mRNA和GATA-3 mRNA(x±s)相对表达量分别为(0.495±0.103)和(0.550±0.119).实验组血浆中IFN-γ的量减少并低于对照组,差异有统计学意义(P<0.05),而IL-4的含量明显高于对照组,差异具有显著性(P<0.001);实验组中T-bet mRNA的相对表达量与对照组相比无明显变化,无统计学意义(P>0.05),而实验组中GATA-3 mRNA相对表达量明显高于对照组,二者比较有统计学意义(P<0.05).结论大鼠变应性鼻炎模型中,GATA-3的过表达导致GATA-3和T-bet表达比例失衡,进而导致Th1/Th2细胞的免疫紊乱,GATA-3和T-bet表达比例失衡可能是变应性鼻炎发生的基因基础.

Objective To investigate the expression of genes T-bet and GATA-3 in blood mononuclear cells（BMCs）in allergic rhinitis rats model at different stages of development of allergic rhinitis and its role in allergic rhinitis.Methods 20 SD rats（including 10 male and 10 female）were randomly divided into 2 groups,experimental group and control group,10 rats in each group.Ten rats in experimental group were sensitized and intranasally challenged by ovalbumin（OVA）,aluminium hydroxide hydrate gel and Bordelella pertussis inactive microorganism suspension（B.pertussis）adjuvants,as allergic rhinitis models,Ten rats in control group were investigated using physiological saline only.Plasma and BMCs were separated from 2 ml blood which was extracted from rat heart at the end of the final challenge.Enzyme linked immunosorbent assay（ELISA）was utilized to detect the levels of IL-4 and IFN-γ,and RT-PCR was used to detect the expression of T-bet and GATA-3 mRNA.Results At the end of final challenge,the levels of IL-4 and IFN-γ（x±s）in experimental group were（14.241±1.963）and（12.364±2.524）Pg /mL,respectively;Both of relative quantitation of expression of T-bet mRNA and GATA-3 mRNA（x±s）in BMCs in experimental group were（0.433±0.514）and（1.029 ±0.690）,respectively.While,in control group,the levels of IL-4 and IFN-γ（x±s）in serum were（4.916±0.600）and（16.303±5.335）Pg/mL,respectively;Both of relative quantitation of expression of T-bet mRNA and GATA-3 mRNA（x±s）were（0.495±0.103）and（0.550±0.119）,respectively.The serum level of IL-4 in experimental group was higher than that in control group,there was a significant difference（P〈0.001）.However,the serum level of IFN-γ was lower than it in control group and there was a significant difference（P〈0.05）.Relative quantitation of expression of T-bet mRNA in BMCs in experimental group had not been changed markedly compared with that in control group and there was no significant difference（P〉0.05）.While,The amount of expression of GATA-3 mRNA in BMCs in experimental group was significantly higher than that in control group（P〈0.05）.Conclusion In allergic rhinitis rat models,the overexpression of GATA-3 causes the imbalance of GATA-3/Fbet ratio,and then leads to Th1/Th2 cells dysfunctio and imbalance of GATA-3/T-bet ration may be genetic base and it plays an important role in the development of allergic rhinitis.