急性期川崎病Th17细胞变化初探

Investigation of the change of Th17 cells during acute phase of Kawasaki disease

目的探讨Th17细胞在川崎病（Kawasaki disease，KD）免疫发病机制中的作用。方法急性期KD患儿60例，正常同年龄对照组32例，KD患儿分别于静脉丙种球蛋白（IVIG）治疗前后直接取血备检。采用荧光定量PCR（real—timePCR）检测CD4^＋T细胞IL-17A／F、转录因子ROR-γt、Foxp3及PBMCIL-6、TGF—β、IL-23p19、IL-27p28、IL-27EBI3、IFN-γ等mRNA表达；酶联免疫吸附试验检测血浆中IL-6、TGF—β、IL-23、IL-27、IFN-γ的蛋白浓度；流式细胞术检测外周血CD4^＋CD25^＋调节性T细胞（Tr）的比例。结果急性期KD患儿CD4^＋T细胞高表达IL-17A及IL-17F（P〈0．01），IVIG治疗后明显降低（P〈0．01）；急性期KD患儿IL-17A／IL-17F与红细胞沉降率（ESR）、C反应蛋白（CRP）、白细胞数目（WBC）呈正相关（IL-17A：0．70，0．85，0．80，P〈0．01；IL一17F：0．63，0．65，0．69，P〈0．01）；急性期KD患儿Th17细胞转录因子ROR-γt及前炎症细胞因子IL-6转录水平明显高于对照组（P〈0．01），IVIG治疗后显著降低（P〈0．01）；TGF—β、IL-23p19、IL-27p28、IL-27EBI3mRNA水平及血浆蛋白浓度与对照组比较差异无统计学意义（P〉0．05）；血浆IFN-γ浓度显著升高，mRNA水平无变化；急性期KD患儿CD4^＋CD25^＋Tr细胞比例明显低于正常对照组（P〈0．01），其转录因子Foxp3表达亦明显降低（P〈0．01）。结论急性期KD患儿Th17细胞过度活化可能参与了KD免疫发病机制。

Objective To investigate the changes and the role of Th17 cells in immunological pathogenesis of Kawasaki Disease （KD）. Methods Sixty children with KD and thirty-two age-matched healthy children were studied. Real-time PCR were used to evaluate the mRNA levels of IL-17A/F, ROR-γt and Foxp3 in CD4-positive cells, or IL-6, TGF-β, IL-23p19, IL-27p28, IL-27EBI3, IFN-γ in peripheral blood mononuclear cells. Protein levels of cytokines in plasma were measured by ELISA. The proportion of CD4^＋CD25^＋ regulatory T （Tr） cells was analyzed by flow cytometry. Results Compared with healthy controls, transcription levels of IL-17A/F were significantly up-regulated during acute phase of KD （P 〈 0.01 ）, and down-regulated after treated with intravenous immunological globulin（IVIG） therapy. Significant positive correlation between IL-17A/F and erythrocyte sedimentation rate （ESR）, C-reactive protein （CRP） and white blood cells（WBC） were observed during acute phase of Kawasaki disease（ IL-17A： 0.70, 0.85, 0.80, P 〈 0.01 ; IL-17F ： 0.63, 0.65, 0.69, P 〈 0.01 ）. Transcription levels of ROR-γt in CD4 ^＋ T cells and proinflammatory cytokine IL-6 in PBMC, and protein level of IL-6 in plasma were significantly increased during acute phase of KD（ P 〈 0.01 ）, and decreased to some extents after IVIG therapy. No differences of TGF-β, IL-23p19, IL-27p28 and IL-27EBI3 mRNA and protein levels in plasma were detected among all groups（ P 〉 0.05 ）. The protein level of IFN-γ in plasma was significantly elevated during acute phase of KD（P 〈 0.01 ）. No change of IFN-γ, mRNA level was observed（ P 〉 0.05 ）. The proportion of CD4 ^＋ CD25 ^＋ Tr cells in peripheral blood from patients with KD was significantly lower than that of healthy subjects （ P 〈 0.01 ）, and increase significantly after treatment of IVIG therapy. Transcription level of Foxp3 was significantly down-regulated in acute phase of KD （ P 〈 0.01 ）, and up-regulated to some extent after IVIG therapy. Conclusion Aberrant activation of Th17 cells may be involved with immunological pathogenesis of KD.