Objective: To investigate the frequencies and subset distribution of peripheral helper (Tph) T cells in patients with immune thrombocytopenia (ITP), and explore the pathogenesis of ITP.
Methods: A total of 25 newly diagnosed ITP patients treated in The Second Affiliated Hospital of Dalian Medical University from January to December 2022 were selected, and 25 healthy volunteers (age- and sex-matched) were recruited as the control group. Flow cytometry was used to detect the subsets of CD4+ T cells and Tph cells.
Results: The frequency of effector memory (CCR7- CD45RO+CD4+) T cells in ITP patients was significantly higher than that in healthy controls(P < 0.05). The frequency of Tph cells in ITP patients was also significantly higher than that in healthy controls (P < 0.001), and most of the Tph cells in ITP patients were effector memory T cells. Furthermore, the expressions of T-cell costimulatory molecules in Tph cells, including ICOS and CD84, were similar to those in follicular helper T(Tfh) cells. CXCR3 - CCR6 -Tph (Tph2) subgroup was dominant in Tph cells, but the frequency of CXCR3+CCR6- Tph (Tph1) cells in ITP patients was much higher than that in healthy controls (P < 0.05).
Conclusion: Tph cells, especially Tph1 cells, were abnormally expanded in ITP patients, which may be a potential etiology of ITP.
题目: ITP患者外周血Tph细胞比例及亚群分析.
目的: 观察免疫性血小板减少症（ITP）患者外周辅助T（Tph）细胞比例及其亚群分布情况，探讨ITP的发病机制。.
方法: 选取2022年1月至2022年12月于大连医科大学附属第二医院就诊的25例ITP患者及25例性别年龄匹配的健康人作为对照，通过流式细胞术分析外周血CD4+ T细胞亚群、Tph细胞比例及其亚群分布情况。.
结果: ITP患者外周血CD4+T细胞中效应记忆T细胞比例明显高于健康对照组（P < 0.05）；ITP患者的Tph细胞比例亦明显高于健康对照组（P < 0.001），且ITP患者Tph细胞大部分为效应记忆T细胞；Tph细胞与Tfh细胞一样表达共刺激分子ICOS和CD84；Tph细胞主要为Tph2亚型，但与健康对照组相比，ITP患者Tph1型细胞比例明显升高（P < 0.05）。.
结论: ITP患者外周血中Tph细胞比例明显升高，尤其是Tph1型细胞比例明显高于健康对照组，Tph细胞的异常可能为ITP的发病机制之一。.
Keywords: peripheral helper T cells; immune thrombocytopenia; CD4+T cells.