原发免疫性血小板减少症患者外周血Treg细胞程序性死亡受体-1的表达

Expression of PD-1 on peripheral blood Treg cells in patients with primary immune thrombocytopenia

目的:检测原发免疫性血小板减少症(immune thrombocytopenia,ITP)患者外周血中的调节性T细胞(regulatory T cells,Treg细胞)百分比以及Treg细胞上程序性死亡受体-1(programmed death-1,PD-1)的表达情况,并探讨其临床意义。方法:将30例确诊的ITP患者依据治疗后血小板计数是否恢复正常分为治疗有效组(21例)和治疗无效组(9例),用流式细胞术分别检测其治疗前后外周血中CD3^+T淋巴细胞计数、Treg细胞百分比及PD-1^+Treg细胞百分比。结果:治疗有效组治疗前、后CD3^+T淋巴细胞计数分别为(6.39±5.74)×10~9/L和(5.49±4.86)×10~9/L(P>0.05);治疗无效组治疗前、后CD3^+T淋巴细胞计数分别为(8.34±2.95)×10~9/L和(7.87±1.47)×10~9/L(P>0.05),治疗有效组与治疗无效组间比较,治疗前比较、治疗后比较的CD3^+T淋巴细胞计数差异无统计学意义。治疗有效组患者外周血中Treg细胞百分比由治疗前的16.96%±4.61%升至32.74%±9.38%,PD-1^+Treg细胞百分比由治疗前的14.88%±6.75%升至29.62%±7.97%,差异均有统计学意义(P<0.000 1)。而治疗无效组患者外周血中Treg细胞比例由治疗前的17.41%±6.77%上调至19.18%±7.64%,PD-1^+Treg细胞比例由治疗前的15.30%±6.57%上调至19.58%±6.91%,但差异均无统计学意义(P>0.05)。接受治疗后,治疗有效组的外周血中Treg细胞百分比及PD-1^+Treg细胞百分比均明显高于无效组(P<0.05)。结论:Treg细胞及PD-1^+Treg细胞可能在ITP的发生、发展中发挥重要作用,检测外周血中这2种细胞的百分比可能提示患者治疗有效。

Objective： To investigate the proportion of regulatory T cells （Treg cells） in peripheral blood and the expression of programmed death receptor-1 （PD-1） on Treg cells in adult primary immune thromboeytopenia（ITP） patients, and to analyze their clinical significance. Methods： Altogether 30 patients with ITP were enrolled and divided into effective group（21 patients）and ineffective group （9 patients）according to whether platelets returned to normal level after treatment. Flow cytometry（FCM） was applied to determine the counts of CD3^＋ T lymphocytes, and proportions of Treg cells and PD-1^＋ Tregcells in ITP patients pre- and post-treatment. Results： The count of CD3^＋ T lymphocytes was not differed significantly before and after treatment in both the effective treatment group [6.39±5.74）x10^9/L vs （5.49±4.86）x10^9/L] and ineffective group[（8.34±2.95）×10^9/L vs （7.87±1,47）±10^9/L]. The proportion of Treg cells increased from 16.96%＋4.61% to 32.74%±9.38% in effective treatment group（P〈0.05）, and the proportion of PD-1＋ Treg cells increased from 14.88%±6.75% to 29.62%＋7.97%（P〈0.05）. In contrast, Treg cells increased a little and maintained at a low level in ineffective group （from 17.41%±6.77% to 19.18%±7.64%, P〉0,05） and PD-1^＋ Treg had no significant increase （from 15.30%±6.57% to 19.58%±6.91%, P〉0.05）. Moreover, the proportions of peripheral blood Treg cells and PD-1^＋ Treg cells in the effective group were significantly higher than those in the ineffective group after treatment （P〈0.05）. Conclusions： Treg cells and PD-1^＋ Treg cells may play an important role in the development and progress of ITP. The detection of proportion of these two cells in peripheral blood might be helpful to predict the prognosis of ITP.