Tim-3及Th-17在儿童急性ITP发病机制中的作用

目的 探讨Tim-3、Th17细胞及Treg细胞在ITP患者中的表达及其临床意义.方法 应用流式细胞术检测42例ITP患者与39名健康对照者Th17细胞及Treg细胞的表达;采用ELISA法检测外周血血浆中IL-17、IFN-γ和IL-4的表达;应用RT-PCR方法 检测Tim-3、IFN-γ、IL-4、T-bet等细胞因子和转录因子的mRNA表达.结果 ITP患者Th17细胞比例为(2.41±1.43)%,明显高于健康对照组的(1.08±0.59)%,差异有统计学意义(t=5.35,P<0.05);ITP患者Treg细胞比例为(1.64±0.74)%,明显低于健康对照组的(3.12±0.52)%,差异有统计学意义(t=10.33,P<0.05).IL-17在ITP患者血浆中的表达水平为(14.42±6.37)ng/L,健康对照组为(13.91±4.47)ng/L,差异无统计学意义(t=0.42,P>0.05);而ITP患者血浆IFN-γ含量为(55.74±15.25)ng/L,较健康对照组的(31.33±12.99)ng/L明显升高,IL-4含量为(7.42±1.50)ng/L,较健康对照组的(18.17±5.19)ng/L明显降低,差异均有统计学意义(t=7.72、2.87,P均<0.05).ITP患者的T-bet mRNA和IFN-γmRNA表达水平明显升高,分别为健康对照组的(3.34±1.32)倍和(8.57±3.44)倍,差异有统计学意义(t=6.41、13.21,P<0.05);而Tim-3 mRNA和IL-4 mRNA表达水平明显下降,分别为健康对照的(0.29±0.15)倍和(0.25±0.15)侪,差异均有统计学意义(t=9.61、10.02,P<0.05).结论 Th17/Treg细胞亚群比例失调和Tim-3的表达下降可能是ITP发生和发展的重要决定因素.

The roles of Tim-3 and Th-17 in children with acute idiopathic thrombocytopenic purpura

Objective To investigate the expression and the role of Tim-3 and Th-17 in ITP patients and to research their clinical application. Methods Total 42 active ITP patients and 39 healthy donors were recruited in this research. The expressions of Th17 and CD4+ CD25+ Treg were measured with flow cytometer. IL-17, IFN-γ levels as well as IL-4 plasma levels were determined by ELISA. The mRNA expression of Tim-3, IFN-γ, IL-4 and T-bet were measured using RT-PCR in all samples. Results The expression of Th17 cells in ITP patients was (2.41 ± 1.43 )%, which was significantly higher than control group ( 1.08 ± 0.59)% ( t = 5.35, P < 0.05 ). But the percentage of Treg in ITP patients was ( 1.64 ±0.74)%, which was lower than control group (3.12 ±0.52)% (t = 10.33, P <0.05). The levels of IL-17 in plasma of ITP and controls were ( 14.42 ±6.37) ng/L and ( 13.91 ±4.47) ng/L respectively (t =0.42, P > 0.05). The level of IFN-γin plasma of ITP was (55.74 ± 15.25 ) ng/L, which was higher than control group (31.33 ± 12.99) ng/L (t = 7.72, P < 0.05 ). The level of IL-4 in the plasma of ITP was (7.42 ± 1.50) ng/L, which was lower than controls ( 18.17 ± 5.19) ng/L ( t = 12.87, P ＜ 0.05 ). Both IFN-γand T-bet mRNA levels were up-regulated in active ITP patients by the factor ( 8.57 ± 3.44 ) -fold and (3.34 ± 1.32)-fold than control group (t = 13.21,6.41 ,P <0.05). The decreases observed in IL-4 and Tim-3 were (0.25 ±0.15 )-fold and (0.29 ±0.15)-fold respectively in ITP patients compared with control group (t=10.02,9.61,P＜0.05 ). Conclusion The imbalance of Th17/Treg and the decrease of Tim-3 might be important determinants in the evolution of ITP.