老年免疫性血小板减少症患者外周血T淋巴细胞亚群检测及其临床意义

Contributions of T lymphocyte abnormalities to therapeutic outcomes in elderly patients with immune thrombocytopenia

目的:检测老年免疫性血小板减少症(ITP)患者外周血中T淋巴细胞亚群及血清免疫球蛋白(IgG)的变化,并探讨其与疗效间的关系。方法:丙种球蛋白(IVIG)及糖皮质激素治疗30例新诊断的老年ITP患者,应用流式细胞术检测20例健康体检者(对照组)及30例老年ITP患者(ITP组)治疗前后外周血中淋巴细胞亚群CD2+、CD3+、CD4+、CD8+、CD19+、NK细胞及CD4+/CD8+的变化。应用酶联免疫吸附法(ELISA)检测血清中免疫球蛋白(IgG)的变化。结果:治疗前,老年ITP患者血清IgG水平及外周血中CD19+细胞的表达明显高于对照组,而CD4+/CD8+细胞比例明显低于对照组。根据疗效,将老年ITP患者分为治疗有效组及无效组,有效组患者血清IgG以及外周血CD19+细胞表达升高,治疗后明显下降。无效组患者除了IgG升高外,CD8+细胞明显升高,CD4+/CD8+细胞比例降低。治疗后IgG水平降至正常水平,但异常T系表达治疗前后无明显改善,且治疗后NK细胞水平明显低于对照组。结论:T细胞免疫异常可能是老年ITP患者一线治疗效果不理想的主要原因,针对不同发病机制进行个体化治疗是今后努力的方向。

Objective：To explore the clinical importance of T lymphocyte subsets in the peripheral blood of elderly patients with newly diagnosed ITP before and after first-line treatment. Method：T lymphocyte subsets in the peripheral blood of 30 newly diagnosed ITP patients and 20 normal controls were detected by flow cytometry. Immunoglobulin G （IgG） levels in peripheral serum were determined by enzyme-linked immuno sorbent assay （ELISA）. 30 elderly ITP patients were treated with intravenous immunoglobulin （IVIG） plus corticosteroids and therapeutic responses were evaluated. Result： Compared with the control group, we observed increased IgG and CD19＋ cell expression and decreased CD4＋/CD8＋ cell ratio in ITP group before treatment. According to treatment responses,ITP patients could be divided into respond and non-respond groups. After treatment, the increased IgG and CD19＋ cell expression could be reduced in both respond and non-respond groups,while CD8＋ cell percentage and CD4＋/CD8＋ cell ratio could not be corrected in non respond ITP patients. Furthermore,there is no change in abnormal T linage expression and even lower NK cell expression found in non-respond elderly patients after treat- ment when compared with that in controls. Conclusion： Our findings suggested that patients with higher levels of CD8＋ cells and lower levels of CD4＋/CD8＋ cell ratio were less likely to respond to first-line treatment. Lower lev- els of NK cells made therapies in elderly ITP patients even more difficult. Different kinds of therapies towards dif- ferent mechanisms are needed in the future.