瘦素通过白细胞介素-6调控类风湿关节炎患者外周血调节性T细胞的增殖

Leptin regulates the proliferati on of peripheral regulatory T cells v/a increasing interleukin-6 in rheumatoid arthritis patients

目的初步探讨瘦素对RA患者外周血调节性T细胞增殖的影响。方法分离培养6例RA患者PBMCs，分别用抗CD3（3 μg/ml）/抗CD28（2 μg/ml）、抗CD3（3 μg/ml）/抗CD28（2 μg/ml）加瘦素（100 ng/ml）、抗CD3（3 μg/ml）/抗CD28（2 μg/ml）以及瘦素（100 ng/ml）加IL-6R拮抗剂（0.5 μg/ml）刺激72 h。收集悬浮细胞，流式细胞术检测调节性T细胞百分率；ELISA检测细胞培养上清中IL-6、TGF-β水平。采用Wilcoxon秩和检验进行统计学分析。结果①与对照组比较，瘦素刺激72 h后调节性T细胞比例下降[13.6（11.6，14.8）%和9.8（7.0，10.0）%，Z=-2.201，P〈0.05]；IL-6、TGF-β水平均上升[548.9（508.6，608.4）ng/L和631.8（538.4，672.6）ng/L，Z=-1.992，P〈0.05；1175.0（1 045.4，1 373.1）ng/L和1 580.2（1 315.3，1 906.5）ng/L，Z=-2.201，P〈0.05]；②加入IL-6R拮抗剂后，瘦素刺激PBMCs分泌IL-6水平下降[631.8（538.4，672.6）ng/L和522.7（339.3，593.3）ng/L，Z=-2.201，P〈0.05]；调节性T细胞比例上升[9.8（7.0，10.0）%和12.3（9.7，13.8）%，Z=-1.997，P〈0.05]。结论瘦素可能通过上调IL-6，进而对外周血调节性T细胞的增殖起到负调控作用。

ObjectiveTo investigate the influence of Leptin on the proliferation of peripheral blood regulatory T cells in patients with rheumatoid arthritis （RA）.MethodsPeripheral blood mononuclear cells （PBMCs） were isolated from 6 RA patients. RA PBMCs were stimulated with anti-CD3 （3 μg/ml）/anti-CD28 （2 μg/ml） antibody for 72 h, anti-CD3 （3 μg/ml）/anti-CD28 （2 μg/ml） antibody and Leptin （100 ng/ml） for 72 h, anti-CD3 （3 μg/ml）/anti-CD28 （2 μg/ml） antibody and Leptin （100 ng/ml） and interleukin （IL）-6 receptor antagonist （0.5 μg/ml） for 72 h. Regulatory T cells （Treg） were detected by flow cetometry. IL-6 level and TGF-β levels in the supernatants of RA PBMCs culture were detected by Enzyme linked immunosorbent assay（ELISA）. Statistical analysis between the two groups were performed by Wilcoxon Signed Rank Test.Results① Our results suggested that compared to the control group, RA PBMCs were stimulated by leptin for 72 h had lower percentage of Treg[13.6（11.6, 14.8）% vs 9.8（7.0, 10.0）%, Z=-2.201, P〈0.05]; Compared to the control group, the level of IL-6 and TGF-β were elevated when RA PBMCs treated with leptin for 72 h [548.9（508.6, 608.4） ng/L vs 631.8 （538.4, 672.6） ng/L, Z=-1.992, P〈0.05; 1175.0 （1 045.4, 1 373.1） ng/L vs 1 580.2 （1 315.3, 1 906.5） ng/L, Z=-2.201, P〈0.05]; ② The percentage of Peripheral Treg was increased [9.8（7.0,10.0）% vs 12.3 （9.7, 13.8）%, Z=-1.997, P〈0.05] and the level of IL-6 was decreased [631.8（538.4, 672.6） ng/L vs 522.7（339.3, 593.3） ng/L, Z=-2.201, P〈0.05] when RA PBMCs was stimulated with IL-6 receptor antagonist and anti-CD3/anti-CD28 antibody and Leptin for 72 h.ConclusionThe study has shown that Leptin can down-regulate the percentage of RA peripheral blood Treg via increasing IL-6 secretion.