Li Jun, Zhou Yong-Ming, Hu Ming-Hui, Sun Wei-Ling, Xue Zhi-Zhong
Department of Hematology, Jiangsu Provincial Hospital of Chinese Traditional Medicine, Nanjing University of Chinese Traditional Medicine, Nanjing 210029, Jiangsu Province, China.
Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2010 Oct;18(5):1211-9.
The study was aimed to explore the effects of T-bet (T-box expressed in T cell), GATA-3(GATA binding protein 3) and relevant signal transduction pathways on the immune-related pathogenesis of chronic aplastic anemia (CAA), and to investigate the immunological regulation mechanism in the treatment of CAA by using cyclosporine A (CsA) at the level of Th cell imbalance, transcriptional factors, and relevant signal pathways. The real-time fluorescent quantitative polymerase chain reaction (real-time FQ-PCR) was used to determine the mRNA expression of T-bet, GATA-3, signal transducers and activators of transcription 4 (STAT4) and signal transducers and activators of transcription 6 (STAT6) in peripheral blood mononuclear cell (PBMNC) of CAA patients before and after treatment with CsA; the flow cytometry (FCM) and enzyme linked immunosorbent assay (ELISA) were used to determine the Th1/Th2 proportion in peripheral blood, and levels of IFN-γ, IL-12 and IL-4 in PBMNC-cultured supernatant. Healthy people were included to test the above indexes. The results showed that the mRNA expression of PBMNC T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, Th1/Th2 ratio and levels of IFN-γ and IL-12 in PBMNC-cultured supernatant of CAA patients were significantly higher than those of healthy people (p < 0.01). After treating with CsA for 6 months of CsA treatment, expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, IFN-γ and IL-12 levels were lower than before, however, the expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion and IFN-γ had not been reduced to normal state. Compared to healthy people, no significant difference existed in the mRNA expression of GATA-3, STAT6, Th2 proportion, as well as level of IL-4 before and after treatment (p>0.05). It is concluded that the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways, as well as Th balance deviating to Th1 excursion play vital roles in the immunological pathogenesis of AA. CsA lowers the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways to correct Th1 hyperpolarization, which may reduce the abnormally activated cell-mediated immunity and relax hematopoietic depression of AA patients.
本研究旨在探讨T-bet（T细胞表达的T盒）、GATA-3（GATA结合蛋白3）及相关信号转导通路在慢性再生障碍性贫血（CAA）免疫相关发病机制中的作用，并从Th细胞失衡、转录因子及相关信号通路水平研究环孢素A（CsA）治疗CAA的免疫调节机制。采用实时荧光定量聚合酶链反应（real-time FQ-PCR）检测CAA患者CsA治疗前后外周血单个核细胞（PBMNC）中T-bet、GATA-3、转录信号转导子和激活子4（STAT4）及转录信号转导子和激活子6（STAT6）的mRNA表达；采用流式细胞术（FCM）和酶联免疫吸附测定（ELISA）检测外周血中Th1/Th2比例以及PBMNC培养上清液中IFN-γ、IL-12和IL-4水平。纳入健康人检测上述指标。结果显示，CAA患者PBMNC中T-bet、STAT4的mRNA表达、T-bet/GATA-3比值、Th1比例、Th1/Th2比值以及PBMNC培养上清液中IFN-γ和IL-12水平均显著高于健康人（p<0.01）。CsA治疗6个月后，T-bet、STAT4的表达、T-bet/GATA-3比值、Th1比例、IFN-γ和IL-12水平较治疗前降低，但T-bet、STAT4的表达、T-bet/GATA-3比值、Th1比例和IFN-γ尚未降至正常水平。与健康人相比，治疗前后GATA-3、STAT6的mRNA表达、Th2比例以及IL-4水平差异无统计学意义（p>0.05）。结论：IFN-γ/T-bet和IL-12/STAT4通路异常激活以及Th平衡偏向Th1偏移在AA免疫发病机制中起重要作用。CsA降低IFN-γ/T-bet和IL-12/STAT4通路的异常激活以纠正Th1极化，这可能减轻AA患者异常激活的细胞免疫并缓解造血抑制。
