1,25(OH)2D3通过STAT5抑制Th17细胞分化的调控作用研究

1,25-(OH)_2D_3 inhibits Th17 cell differentiation via STAT5 signaling

目的研究1.25二羟基维生素D3[1,25(OH)_2D_3]抑制辅助性T细胞17(Th17)的分化与STAT5调控的关系。方法通过分选出的CD4+T细胞,在1,25(OH)_2D_3和/或STAT5抑制剂的作用下,采用ELISA法检测抑制剂处理后细胞培养上清液Th17细胞因子(IL-17A、IL-22)水平的变化;采用细胞免疫荧光技术检测STAT5的磷酸化水平,采用Western blot技术检测STAT5蛋白表达水平。结果 1,25(OH)_2D_3组细胞培养上清IL-17A和IL-22水平(12.5±0.5 ng/ml,48.5±0.9 pg/ml)明显低于对照组(22.7±0.5 ng/ml,73.8±1.9 pg/ml),而STAT5抑制剂组IL-17A和IL-22水平明显升高(33.5±0.7 ng/ml,89.1±1.4 pg/ml),1,25(OH)_2D_3与STAT5抑制剂联合作用细胞IL-17A和IL-22水平(18.5±0.7 ng/ml,54.1±1.6 pg/ml)显著高于1,25(OH)_2D_3组,但低于STAT5抑制剂组,差异有统计学意义(P<0.01);1,25(OH)_2D_3组细胞p-STAT5表达显著强于对照组,1,25(OH)_2D_3联合STAT5抑制剂组p-STAT5表达量低于对照组,而STAT5抑制剂组细胞p-STAT5表达量最低;1,25(OH)_2D_3组STAT5蛋白表达明显升高,而1,25(OH)_2D_3联合STAT5抑制剂组或STAT5抑制剂组STAT5蛋白表达明显降低,以STAT5抑制剂组细胞表达最弱,差异均具有统计学意义(P<0.01)。结论 1,25(OH)_2D_3通过STAT5信号通路能抑制Th17细胞分化。

Objective To explore the role of 1,25-（OH）2D3 in inhibiting T helper cell 17 （Th17） differentiation and the role of STAT5 in this process. Methods Sorted CD4^＋T cells were treated with 1,25-（OH）2D3 and/or STAT5 inhibitors. The Th17 cytokines （IL-17A,IL-22） levels in supernatants were detected by ELISA; the phosphorylation level of STAT5 was examined by cell immunofluorescenee,and Western blot was used to detect STAT5 protein expression. Results The levels of IL-17A and IL-22 in 1,25-（OH）2D3-treated group were significantly lower than those in the control group [（12.5±0.5） ng/ml and （22.7±0.5） pg/ml vs. （48.5±0.9） ng/ml and （73.8±1.9） pg/ml,respeetively,P〈0.01],while in STAT5 inhibitor-treated group had higher levels of IL-17A [（33.5±0.7） ng/ml] and IL-22 [（89.1±1.4） pg/ml,P〈0.05];IL-17A [（18.5±0.7） ng/ml] and IL-22 [（54.1±1.6） pg/ml] levels in cells treated with 1,25 （OH）2D3 combined with STAT5 inhibitor were significantly higher than those in 1,25-（OH）2D3-treated alone,whereas lower than those in STAT5 inhibitor-treated cells （P〈0.01 for both）;the expression of p-STAT5 was higher in 1,25-（OH）2D3-treated cells and lower in 1,25-（OH）gD3 combined with STAT5 inhibitor-treated cells,while in STAT5 inhibitor-treated cells had the lowest p-STAT5; the STAT5 protein expression was significantly higher in 1,25-（OH）2D3-treated cells,whereas lower in 1,25-（OH）2D3 combined with STAT5 inhibitor-treated cells or in STAT5 inhibitor-treated cells had the lowest STAT5 protein expression （P〈0.01 for all）. Conclusion 1,25-（OH）2D3 might inhibit Thl7 cell differentiation via STAT5 signaling pathway.