口腔扁平苔藓患者外周血CD4+T淋巴细胞组蛋白乙酰化的意义

Aberrant histone modification in peripheral blood CD4+T lymphocytes in oral lichen planus

目的研究口腔扁平苔藓(oral lichen planus,OLP)患者外周血CD4+T淋巴细胞组蛋白乙酰化水平及组蛋白去乙酰化酶(histone deacetylases,HDACs)活性,探讨其在OLP发病中的作用。方法收集2016年8月—2017年1月于南方医科大学口腔医院就诊,经临床及组织病理学诊断为OLP的23例患者(包括11例非糜烂型OLP及12例糜烂型OLP,OLP组)以及10例健康志愿者的外周血(对照组),采用免疫磁珠分离CD4+T淋巴细胞并提取组蛋白和核蛋白,采用ELISA方法检测组蛋白H3/H4乙酰化水平的变化及HDACs活性,并比较分析其在OLP组及对照组的表达差异。结果 OLP组外周血CD4+T淋巴细胞组蛋白H3乙酰化水平低于对照组,差异有统计学意义(u=-2.410,P=0.012),而OLP组与对照组的外周血CD4+T淋巴细胞组蛋白H4乙酰化水平差异无统计学意义(u=-1.412,P=0.158);OLP外周血CD4+T淋巴细胞HDACs活性较对照组高,差异有统计学意义(F=5.749,P=0.023),其中糜烂型OLP研究对象外周血HDACs活性水平高于非糜烂型OLP组(P=0.014)和对照组(P=0.001);OLP组的组蛋白H3乙酰化水平与HDACs酶活性存在负相关关系(rs=-0.771,P<0.001),但健康对照组的组蛋白H3乙酰化水平与HDACs酶活性无相关关系(rs=0.382,P=0.276);OLP组的组蛋白H4乙酰化水平与HDACs酶活性无相关关系(rs=0.149,P=0.498),对照组的组蛋白H4乙酰化水平与HDACs酶活性也无相关关系(rs=0.527,P=0.117)。结论 OLP患者外周血CD4+T淋巴细胞存在组蛋白乙酰化异常且与HDACs活性相关,提示组蛋白乙酰化的表观遗传修饰可能与OLP的发病密切相关。

Objective To investigate the histone acetylation level and histone deacetylase（HDAC） activity of peripheral blood CD4＋T lymphocytes in patients with oral lichen planus（OLP）. Methods Twenty-three OLP patients were selected from August 2016 to January 2017 from the Stomatological Hospital, Southern Medical University. The diagnosis was confirmed by pathology, and the lesions were divided into a nonerosive OLP group（11 cases） and an erosive OLP group（12 cases）. Ten healthy sex-and age-matched volunteers served as controls. Immunomagnetic beads were used to separate CD4＋T lymphocytes, and histones and nucleoproteins were extracted. The global histone H3/H4 acetylation levels and HDAC activity of CD4＋T lymphocytes from all subjects were detected by ELISA. The differences between the OLP and control groups were statistically analyzed. Results Global histone H3 hypoacetylation was observed in the OLP group compared with the control group（u =-2.410, P = 0.012）. However, there was no significant difference in the serum CD4＋T lymphocyte histone H4 acetylation level between the OLP and control group（u =-1.412,P = 0.158）. HDAC activity was significantly higher in the OLP group than in the healthy control group（F = 5.749, P =0.023）, and much higher HDAC activity was observed in the erosive group than in the nonerosive（P = 0.014） and healthy control groups（P = 0.001）. The degree of histone H3 acetylation correlated negatively with increased HDAC activity in the OLP group（rs=-0.771, P 0.001）. There was no correlation between the level of histone H3 acetylation and HDAC activity in the healthy control group（rs= 0.382,P = 0.276）. The histone H4 acetylation level in the OLP group showed no correlation with HDAC activity（rs= 0.149, P = 0.498）, and the histone H4 acetylation level in the control group also showed no correlation with HDAC activity（rs= 0.527, P = 0.117）. Conclusion Abnormal histone acetylation of CD4＋T lymphocytes in the peripheral blood of patients with OLP was identified and could be related to HDAC activity, suggesting that the epigenetic modification of histone acetylation may play a role in the pathogenesis of OLP.