Objective: This study aimed to investigate the ratio of T helper cell 17 (Th17) and regulatory T cells (Treg) in peripheral blood of oral lichen planus (OLP) and explore the pathogenesis of its possible role and significance.
Methods: The peripheral blood samples were obtained from 33 patients with OLP (15 cases of reticular OLP and 18 cases of erosive OLP) and 17 healthy controls. The percentages of Th17 and Treg cells were detected by flow cytometry (FCM). Real-time fluorescence quantitative polymerase chain reaction (qPCR) technique was used to detect the expression levels of retinoid-related orphan nuclear receptor γt (RORγt) and forkhead box 3 (Foxp3).
Results: The proportions of Th17, Treg cells, and their transcription factors (RORγt and Foxp3) in OLP were higher than those in the control groups (P<0.05). By contrast, in Treg cells and Foxp3, no significance was observed between erosive OLP and reticular OLP. Th17/Treg ratio increased in OLP. This ratio was significantly increased in erosive OLP compared with those in the control groups and reticular OLP (P<0.01). Nevertheless, no significance was noted between reticular OLP and control groups. Statistical analysis demonstrated positive correlations among Th17 cells, Th17/Treg, and clinical characteristics (r=0.66, P=0.00; r=0.66, P=0.00; r=0.52, P=0.00; r=0.50, P=0.00). Positive correlations also existed between Th17 and Treg cells (r=0.39, P=0.03).
Conclusions: Th17 cells, Treg cells, and their ratios all increased in the peripheral blood of OLP. Moreover, the imbalance inTh17/Treg may play a role in the pathogenesis of erosive OLP.
目的 了解口腔扁平苔藓（OLP）患者外周血中辅助性T细胞17（Th17）与调节性T细胞（Treg）的平衡变化，探讨它们在OLP发病机制中的作用及意义。方法 选取17例正常组和33例OLP患者（网纹型15例，糜烂型18例）的外周血，应用流式细胞术（FCM）检测Th17、Treg细胞的表达水平，实时荧光定量聚合酶链反应（qPCR）检测它们的转录因子维甲酸相关孤核受体γt（RORγt）和叉头状转录因子3（Foxp3）mRNA的表达。结果 OLP外周血中Th17、Treg细胞及RORγt、Foxp3 mRNA表达均升高（P<0.05），但Treg细胞和Foxp3 mRNA表达在OLP两型间差异无统计学意义。Th17/Treg比值在OLP中升高（P<0.05），其中糜烂型OLP显著高于正常组及网纹型OLP（P< 0.01），但网纹型OLP与正常组相比差异无统计学意义。Spearman相关分析显示Th17细胞和Th17/Treg比值与体征计分、RAE计分存在正相关关系（r=0.66，P=0.00；r=0.66，P=0.00；r=0.52，P=0.00；r=0.50，P=0.00）；同时Th17细胞与Treg细胞也存在正相关关系（r=0.39，P=0.03）。结论 OLP外周血中Th17和Treg细胞以及它们的比例均增高，Th17/Treg失衡在糜烂型OLP的发病过程中起了一定作用。.
Keywords: T helper cell 17; flow cytometry; oral lichen planus; regulatory T cells.