目的：探索难治性免疫性血小板减少症患者外周血中调节性T细胞数量的变化，明确二者之间是否存在相关性。方法：采用流式细胞仪分别检测21例健康人，21例难治性ITP患者CD4⁺CD25⁺细胞和CD4⁺CD25⁺Foxp3⁺细胞的表达水平，将两组计量资料进行统计学分析。结果：难治性ITP患者中外周血CD4⁺CD25⁺细胞比例(4.52 ± 2.95)%、CD4⁺CD25⁺Foxp3⁺占CD4⁺细胞比例(2.30 ± 0.72)%，与正常对照组相比，均明显下降，差异具有统计学意义(P < 0.001, 0.05)，与血小板下降数量无相关性(P > 0.05)。结论：难治性ITP患者体内调节性T细胞数量下降，考虑体内存在自身反应亢进，可破坏血小板，但两者无相关性，这可能也是导致ITP难治的原因之一。
Objective: To explore the expression of regulatory T cells in peripheral blood in patients with re-fractory immune thrombocytopenia (ITP) and the association between them. Methods: 21 patients with refractory ITP and 21 health controls were studied. The expressions of CD4⁺CD25⁺ cells and CD4⁺CD25⁺Foxp3⁺ cells were detected by flow cytometry. Statistical analysis was carried out with regard to data in two groups. Results: The ratios of CD4⁺CD25⁺ cells and CD4⁺CD25⁺Foxp3⁺ cells/ CD4+ cells in patients with refractory ITP decreased significantly compared with those in the con-trol group ((4.52 ± 2.95)% vs (6.33 ± 2.93)%, P < 0.001; (2.30 ± 0.72)% vs (4.17 ± 1.23)%, P < 0.05). There was no correlation between platelet counts and Treg cells. Conclusions: Detection of Treg cells in patients with refractory ITP can induce the hyper auto-reactive activation and more damages of platelets, but they don’t have relations, which may be one reason of refractory ITP.