卡介苗对支气管哮喘患者外周血单个核细胞Th1/Th2平衡的影响

Effects of Bacillus Calmette-Guerin on Th1/Th2 Balance of Peripheral Blood Mononuclear Cells in Patients with Atopic Asthma

目的:研究减毒活菌卡介苗(BCG)干预对支气管哮喘患者外周血单个核细胞Th1/Th2平衡的影响。方法:抽取哮喘患者(哮喘组)外周血样本20例,同期健康献血员(对照组)外周血样本10例。分离外周血淋巴细胞并用BCG(100mg/L)干预培养,于培养前后分别采用流式细胞仪测定外周血Th1、Th2百分率及Th1/Th2比,逆转录聚合酶链反应(RT-PCR)测定培养前后外周血淋巴细胞白细胞介素(IL)-4和干扰素(IFN)-γ表达水平。结果:哮喘组经BCG干预前Th1百分率和Th1/Th2均低于对照组,Th2细胞百分率高于对照组;干预后,Th1百分率和Th1/Th2均升高,Th2细胞百分率降低,差异均有统计学意义(P<0.05)。哮喘组经BCG干预前IFN-γmRNA表达水平低于对照组,IL-4mRNA表达水平高于对照组;干预后,IFN-γmRNA表达水平升高,IL-4mRNA表达水平显著降低,差异均有统计学意义(P<0.05)。结论:哮喘患者中Th2型免疫应答占优势,卡介苗干预可在基因表达水平和细胞数量上纠正哮喘患者的Th1/Th2失衡。

Objective： To investigate the effects of Bacillus Calmette-Guerin （BCG） on the Thlfrh2 balance of human peripheral blood mononuclear cells （PBMC） in asthmatic patients. Methods： PBMC were separated from 20 bronchial asthma patients and 10 non-atopic, age matched healthy control subjects. PBMC were cultured with BCG （100 mg/L） for 48 h as positive group and PBMC were treated by saline as negative group. The mRNA expressions of interleukin-4 （IL-4） and interfer- on-γ （IFN-γ） were measured by reverse transcription-polymerase chain reaction （RT-PCR）, and the peripheral blood Th1/ Th2 lymphocyte ratio was measured using three-color flow cytometry method. Results： Before treatment with BCG, the percentage of Thl and Thl/Th2 were lower in asthma group compared with those of control group （P 〈 0.05） while the percentage of Th2 was significantly higher in asthma group than that in control group （P 〈 0.05）. After stimulation with BCG the percent- age of Thl and Th1/Th2 ratio increased （P 〈0.05）. Also the percentage of Th2 decreased compared with that of untreated asth- ma group （P 〈 0.05）. mRNA expression of IL-4 was significantly higher in asthma group than that in healthy subjects while the mRNA expression of IFN-γwas significantly lower in asthma group than that of control （all P 〈 0.05）. And after BCG stimulation, the IL-4mRNA expression decreased significantly but IFN-γ mRNA expression increased significantly in asthma group compared with those of untreated asthma group （ all P 〈 0.05）. Conclusion： The Th2 immune response is stronger than Thl immune response in bronchial asthma patients. BCG can retrieve the excursion of Th1/Th2 in level of gene expression and cell number.