Division of Clinical Immunology, 3rd Department of Medicine, Medical and Health Science Centre, University of Debrecen, Hungary.
Scand J Rheumatol. 2010 Nov;39(6):490-7. doi: 10.3109/03009741003781951. Epub 2010 Jul 8.
The aim of this study was to perform a quantitative and functional analysis of natural CD4+CD25(high)Foxp3+ regulatory T cells (nTregs) and CD4+IL-17+ T cells, and to assess the serum levels of proinflammatory cytokines in patients with undifferentiated connective tissue disease (UCTD) before and after 5 weeks of 0.5 μg/day alfacalcidol supplementation.
Twenty-five patients with UCTD were enrolled in an open-label trial of alfacalcidol. Plasma levels of 25-hydroxyvitamin D [25(OH)D] were assessed by a high-performance liquid chromatography (HPLC) method. Flow cytometry was used for the quantification of nTregs and the IL-17 expression of T-helper (Th)17 cells. The serum concentrations of cytokines interleukin (IL)-12, interferon (IFN)-γ, IL-23, IL-17, IL-6, and IL-10 were measured by an enzyme-linked immunosorbent assay (ELISA).
Treatment with alfacalcidol raised 25(OH)D levels from a mean of 23.5 ± 5.6 to 34.5 ± 7.4 ng/mL (p = 0.059; NS). Alfacalcidol treatment decreased both Th1- (IL-12 and IFN-γ) and Th17-related (IL-23, IL-17, IL-6) cytokine levels in UCTD patients, while the soluble IL-10 level increased (IL-12: 156.7 ± 75.2 vs. 87.5 ± 42.1 pg/mL, p < 0.001; IFN-γ: 41.5 ± 12.0 vs. 21.7 ± 9.9 pg/mL, p < 0.001; IL-23: 385.2 ± 82.2 vs. 210.0 ± 69.3 pg/mL, p < 0.001; IL-17: 37.8 ± 9.6 vs. 17.8 ± 4.5 pg/mL, p = 0.009; IL-6: 39.4 ± 11.3 vs. 23.5 ± 6.3 pg/mL, p < 0.001, IL-10: 8.4 ± 3.0 vs. 21.4 ± 9.7 pg/mL, p < 0.001). Alfacalcidol improved the Th17/nTreg imbalance, as it inhibited the IL-17 expression of Th17 cells, and increased the number of nTregs. The alfacalcidol might increase the capacity of nTreg cells to suppress the proliferation of autologous CD4+CD25⁻ cells.
Our findings support the idea that vitamin D influences the Th17/nTreg imbalance in vitamin D-insufficient patients with UCTD and could be beneficial in the management of the disease.
本研究旨在对天然 CD4+CD25(high)Foxp3+调节性 T 细胞（nTregs）和 CD4+IL-17+T 细胞进行定量和功能分析，并评估未经分化的结缔组织病（UCTD）患者在接受 0.5 μg/天阿尔法骨化醇补充治疗 5 周前后的血清中促炎细胞因子的水平。
25 例 UCTD 患者参与了阿尔法骨化醇的开放性试验。采用高效液相色谱法（HPLC）测定血浆 25-羟维生素 D [25(OH)D]水平。采用流式细胞术定量测定 nTregs 和 Th17 细胞的 IL-17 表达。采用酶联免疫吸附试验（ELISA）测定细胞因子白细胞介素（IL）-12、干扰素（IFN）-γ、IL-23、IL-17、IL-6 和 IL-10 的血清浓度。
阿尔法骨化醇治疗使 25(OH)D 水平从平均 23.5±5.6ng/mL 升高至 34.5±7.4ng/mL（p=0.059；NS）。阿尔法骨化醇治疗降低了 UCTD 患者的 Th1-（IL-12 和 IFN-γ）和 Th17 相关（IL-23、IL-17、IL-6）细胞因子水平，而可溶性 IL-10 水平升高（IL-12：156.7±75.2 与 87.5±42.1pg/mL，p＜0.001；IFN-γ：41.5±12.0 与 21.7±9.9pg/mL，p＜0.001；IL-23：385.2±82.2 与 210.0±69.3pg/mL，p＜0.001；IL-17：37.8±9.6 与 17.8±4.5pg/mL，p=0.009；IL-6：39.4±11.3 与 23.5±6.3pg/mL，p＜0.001，IL-10：8.4±3.0 与 21.4±9.7pg/mL，p＜0.001）。阿尔法骨化醇改善了 Th17/nTreg 失衡，因为它抑制了 Th17 细胞的 IL-17 表达，并增加了 nTreg 的数量。阿尔法骨化醇可能会增加 nTreg 细胞抑制自身 CD4+CD25-细胞增殖的能力。
我们的研究结果支持维生素 D 影响维生素 D 不足的 UCTD 患者中 Th17/nTreg 失衡的观点，并且可能对疾病的治疗有益。
