Olivito Biagio, Simonini Gabriele, Ciullini Sara, Moriondo Maria, Betti Letizia, Gambineri Eleonora, Cantarini Luca, De Martino Maurizio, Azzari Chiara, Cimaz Rolando
Department of Paediatrics, Rheumatology and Immunology Unit, University of Florence, Anna Meyer Children's Hospital, Florence, Italy.
J Rheumatol. 2009 Sep;36(9):2017-24. doi: 10.3899/jrheum.090066. Epub 2009 Jul 31.
To investigate the relationship between interleukin 17 (IL-17) producing T cells (Th17) and CD4+CD25+FOXP3+ regulatory T cells (Tregs) in blood and synovial fluid (SF) of patients with juvenile idiopathic arthritis (JIA).
Sixty-five children with JIA (18 males and 47 females, median age 6.2 yrs; 45 with oligoarticular and 20 with polyarticular course) and 75 age- and sex-matched healthy controls were studied. Flow cytometry was used to analyze the forkhead box P3 (FOXP3)-positive Treg cells in peripheral blood (PB) and synovial fluid mononuclear cells (SFMC). FOXP3 and retinoic-acid related orphan receptor C isoform 2 (RORC2) messenger RNA (mRNA) were assessed by real-time polymerase chain reaction analysis. Cytokines (IL-17 and Th1/Th2 related cytokines) were measured in culture supernatants of 11 paired PBMC and SFMC activated with PMA and ionomycin.
FOXP3+ T cells and FOXP3 mRNA amounts were significantly lower in PB of children with JIA as compared with controls (p = 0.0002 and p = 0.001, respectively) and a higher percentage of Treg cells with concomitant higher level of FOXP3 transcript levels were observed in SF when compared with their PB counterparts (both p < 0.0001). SF CD4+FOXP3+ T cells were characterized by higher amounts of FOXP3 protein per cell when compared with peripheral CD4+FOXP3+ T cells, as revealed by the difference in FOXP3 median fluorescence intensity (median +/- SD, arbitrary units, 54 +/- 22.6 vs 19.5 +/- 4.2; p < 0.001). RORC2 transcript levels were higher in JIA joints when compared with matched PB samples (median fold increase 3.9, p < 0.0001) but negatively correlated with FOXP3 mRNA levels (r = -0.623, p = 0.04). Stimulated SFMC displayed an impaired ability to produce IL-17 when compared with PBMC and, interestingly, an inverse relationship between IL-17 levels and the percentage of CD4+CD25+FOXP3+ SF T cells (r = -0.510, p = 0.047) was seen.
We demonstrated for the first time an increased synovial expression of the transcription factor of Th17, RORC2, in JIA, and its inverse relationship with FOXP3 mRNA. These results extend research on "Th17" and Tregs in JIA.
探讨幼年特发性关节炎（JIA）患者血液和滑液中产生白细胞介素17（IL-17）的T细胞（Th17）与CD4 + CD25 + FOXP3 +调节性T细胞（Tregs）之间的关系。
研究了65例JIA患儿（男18例，女47例，中位年龄6.2岁；45例为少关节型，20例为多关节型病程）和75例年龄及性别匹配的健康对照。采用流式细胞术分析外周血（PB）和滑液单核细胞（SFMC）中叉头框P3（FOXP3）阳性调节性T细胞。通过实时聚合酶链反应分析评估FOXP3和视黄酸相关孤儿受体C亚型2（RORC2）信使核糖核酸（mRNA）。在用佛波酯（PMA）和离子霉素激活的11对PBMC和SFMC的培养上清液中检测细胞因子（IL-17及Th1/Th2相关细胞因子）。
与对照组相比，JIA患儿PB中的FOXP3 + T细胞和FOXP3 mRNA量显著降低（分别为p = 0.0002和p = 0.001），并且与PB中的对应细胞相比，SF中观察到更高比例的Treg细胞以及更高水平的FOXP3转录物水平（两者p < 0.0001）。与外周CD4 + FOXP3 + T细胞相比，SF CD4 + FOXP3 + T细胞的特征是每个细胞中FOXP3蛋白量更高，这通过FOXP3中位荧光强度的差异得以揭示（中位值±标准差，任意单位，54±22.6对19.5±4.2；p < 0.001）。与匹配的PB样本相比，JIA关节中的RORC2转录物水平更高（中位增加倍数3.9，p < 0.0001），但与FOXP3 mRNA水平呈负相关（r = -0.623，p = 0.04）。与PBMC相比，受刺激的SFMC产生IL-17的能力受损，有趣的是，观察到IL-17水平与CD4 + CD25 + FOXP3 + SF T细胞百分比之间呈负相关（r = -0.510，p = 0.047）。
我们首次证明JIA中Th17转录因子RORC2的滑膜表达增加，并且它与FOXP3 mRNA呈负相关。这些结果扩展了对JIA中“Th17”和Tregs的研究。
