Ren Yue, Fu Rong, Wang Huaquan, Liu Hui, Wang Yihao, Qi Weiwei, Tao Jinglian, Shao Zonghong
Department of Hematology,General Hospital, Tianjin Medical University, Tianjin 300052, China.
Department of Hematology, General Hospital, Tianjin Medical University, Tianjin 300052, China.
Zhonghua Yi Xue Za Zhi. 2014 Jul 22;94(28):2165-8.
To explore the global DNA methylation and the expression of regulatory genes for methylation in CD4⁺ T cells of the patients with immune related pancytopenia (IRP) and explore the role of methylation in the pathogenesis of IRP.
Thirty IRP patients (untreated, n = 15; remission, n = 15) and 15 healthy donors as controls were enrolled from December 2012 to December 2013. CD4⁺ T cells were sorted by immunomagnetic separation. The global DNA methylation was tested with enzyme-linked immunosorbent assay (ELISA). The mRNA levels of DNA methylation-related regulating genes, DNA methyltransferases (DNMTs) and methylated CpG binding proteins (MBDs), were measured by real-time quantitative-polymerase chain reaction (RT-PCR).
The level of global DNA methylation in peripheral blood CD4⁺ T cells of untreated IRP patients (3.525% ± 2.046%) and remission patients (4.790% ± 1.471%) were significantly lower than that of normal controls (10.101% ± 3.449%) respectively (both P < 0.05). DNMT3b mRNA level of untreated IRP patients (1.332 ± 0.785) was significantly lower than that of normal controls (2.077 ± 1.059) in CD4⁺ T cells (P < 0.05). The mRNA expression of MBD2 was significantly higher in CD4⁺ T cells from untreated and remission IRP patients (2.999 ± 1.601, 2.055 ± 1.576) than that in controls (0.581 ± 0.247) (both P < 0.05). The MBD4 mRNA level was significantly higher in CD4⁺ T cells from untreated IRP patients (2.736 ± 2.719) compared to that in normal controls (1.167 ± 1.006) (P < 0.05). DNMT3b mRNA expression and CD4⁺ T cell DNA methylation to be positive correlated within IRP patients (r = 0.569, P < 0.01). The MBD2 mRNA expression was negatively correlated with CD4⁺ T cell DNA methylation and the ratio of Th1/Th2 (r = -0.763, P < 0.01; r = -0.652, P < 0.05) . The global methylation of CD4⁺ T cells negatively related to the ratio of CD5⁺ B cells (r = -0.439, P < 0.05).
The globe DNA hypomethylation and abnormal expression of DNA methylation-related enzymes in peripheral blood CD4⁺ T cells may be related with the pathogenesis of IRP.
探讨免疫相关性全血细胞减少症（IRP）患者CD4⁺T细胞中整体DNA甲基化及甲基化调控基因的表达情况，以探究甲基化在IRP发病机制中的作用。
选取2012年12月至2013年12月期间收治的30例IRP患者（未治疗组，n = 15；缓解组，n = 15）及15名健康供者作为对照。采用免疫磁珠分选法分离CD4⁺T细胞。采用酶联免疫吸附测定（ELISA）检测整体DNA甲基化水平。采用实时定量聚合酶链反应（RT-PCR）检测DNA甲基化相关调控基因、DNA甲基转移酶（DNMTs）和甲基化CpG结合蛋白（MBDs）的mRNA水平。
未治疗IRP患者外周血CD4⁺T细胞中整体DNA甲基化水平（3.525% ± 2.046%）及缓解期患者（4.790% ± 1.471%）均显著低于正常对照组（10.101% ± 3.449%）（均P < 0.05）。未治疗IRP患者CD4⁺T细胞中DNMT3b mRNA水平（1.332 ± 0.785）显著低于正常对照组（2.077 ± 1.059）（P < 0.05）。未治疗及缓解期IRP患者CD4⁺T细胞中MBD2的mRNA表达（2.999 ± 1.601，2.055 ± 1.576）显著高于对照组（0.581 ± 0.247）（均P < 0.05）。未治疗IRP患者CD4⁺T细胞中MBD4 mRNA水平（2.736 ± 2.719）显著高于正常对照组（1.167 ± 1.006）（P < 0.05）。IRP患者中DNMT3b mRNA表达与CD4⁺T细胞DNA甲基化呈正相关（r = 0.569，P < 0.01）。MBD2 mRNA表达与CD4⁺T细胞DNA甲基化及Th1/Th2比值呈负相关（r = -0.763，P < 0.01；r = -0.652，P < 0.05）。CD4⁺T细胞整体甲基化与CD5⁺B细胞比值呈负相关（r = -0.439，P < 0.05）。
外周血CD4⁺T细胞中整体DNA低甲基化及DNA甲基化相关酶的异常表达可能与IRP的发病机制有关。
