人T淋巴细胞活化后羟甲基化的变化  

Changes of 5-hydroxymethylcytosine and 5-methylcytosine in activated human T lymphocytes

作　　者：张庆[1,2] 史震[1] 李小翠[1] 刘晓梅[1] 汤仁仙[1] 郑葵阳[1] 周峰[1] 

机构地区：[1]徐州医学院病原生物学与免疫学教研室感染与免疫实验室,221004 [2]徐州市肿瘤医院检验科,221002

出　　处：《免疫学杂志》2014年第11期975-978,共4页Immunological Journal

基　　金：江苏省科技厅自然科学基金面上项目(BK20141136);江苏省脑病重点实验室开放研究课题(JSBL1205);徐州医学院专项人才基金(2012KJZ02)

摘　　要：目的初步探讨人T淋巴细胞活化后细胞内5-羟甲基胞嘧啶(5-hydroxymethylcytosine,5-hmC)和5-甲基胞嘧啶(5-methylcytosine,5-mC)的含量变化。方法成年健康人外周血单个核细胞(peripheral blood mononuclear cell,PBMCs)分别经刀豆蛋白(ConA)或CD3抗体和CD28抗体处理72 h后,采用免疫荧光法观察5-hmC和5-mC的变化,Real-time PCR检测TETs的mRNA转录水平。结果免疫荧光结果显示无论是经ConA非特异性刺激还是经CD3抗体和CD28抗体处理的人T淋巴细胞细胞核内,5-hmC水平明显高于5-mC,且后者从核内转位到胞浆;CD3抗体和CD28抗体处理后的TET2 mRNA转录水平显著高于非处理组。结论活化的T淋巴细胞中5-mC转变是由TET2调控的。The epigenetically important DNA modification of 5- methylcytosine（ 5mC） from 5-hydroxymethylcytosine（5hmC） occurs via a stepwise process with the aid of ten-eleven translocation（Tet） enzymes.Recent studies have revealed that demethylation of 5hmC plays essential roles in diverse development processes and diseases. It is currently unknown whether Tet-induced 5hmC plays a role in activated human T lymphocytes.Here, we explored expression of 5hmC and 5mC by immunofluoresent assay and determined TETs gene expression by real-time PCR assay in human PBMCs treated with ConA protein or with anti-CD3 plus anti-CD28 antibodies.Results showed that the expression of 5hmC was dramatically higher than with 5mC in the cytoplasuy of activated human T lymphocytes. This elevated expression strongly correlated with increased expression of the TET2 enzyme,which responded positively to anti-CD3/CD28 stimulation. Other TETs（TET1 and TET3） were unaffected by the anti-CD3/CD28 activity. These data suggest that TET2 is involved in 5mC stepwise to 5hmC, which contributes to activation of T cells.

关 键 词：5-羟甲基胞嘧啶 5-甲基胞嘧啶 TETs T淋巴细胞 

分 类 号：R392[医药卫生—免疫学]