强直性脊柱炎骨髓间充质干细胞诱导Th17/Treg失衡

摘要

Objective To observe interleukin (IL)-17 and IL-23 expression levels in peripheral blood of ankylosing spondylitis(AS) patients,and investigate the interaction between bone marrow-derived mesenchymal stem cels(BMSCs) and CCR4+CCR6+ Th(Th17)/Treg cellsin vitro to offer theoretical basis for clarifying the pathogenesis and searching new therapy target of AS.Methods Forty-eight AS patients(5 females and 43 males) with the age of 26.2±5.2 years and 49 healthy donors(HDs()5 females and 44 males) with the age of 25.9±4.8 years were included in the study. All of the AS patients were HLA-B27+;conversely,43 healthy donors HLA-B27+(HD1) and 6 healthy donors HLA-B27-(HD2). IL-17 and IL-23 expression levels were examined by ELISA assay,and frequency and phenotype of Th17/Treg cels in the peripheral blood were assayed using flow cytometry. The peripheral blood mononuclear cells(PBMCs) of HD were isolated and were co-cultured with BMSCs isolated from AS patients or HD respectively for 72 hin vitro,then the PBSCs were collected and assayed using flow cytometry.Results Compared to the 49 HDs,the AS patients at active stage showed normal IL-17 and IL-23 expression levels(P>0.05);however,the frequencies of Treg in AS-PBMCs decreased,while Th17 cels increased(P<0.05). Th17 cels decreased and Treg cels increased slightly in the PBMCs that were co-cultured with BMSCs of healthy donors for 72 h(P>0.05). While,Compared to the 49 HDs and no co-cultured PBMCs,Th17 cels increased with Treg cels decreased significantly in the PBMCs that were co-cultured with BMSCs of AS patients for 72 h(P<0.05).Conclusion Th17/Treg cell subset is imbalanced in the PBMCs of AS patients,and the BMSCs of AS with reduced immunomodulation potential may be involved and play a important role in pathogenesis of AS via inducing the two cell subset imbalance.%目的：观察强直性脊柱炎（AS）患者外周血白介素（IL）-17A、IL-23水平及Th17/Treg比例，探讨骨髓间充质干细胞（BMSCs）与Th17/Treg体外相互作用，为研究AS发生机制提供理论依据。方法研究对象为48例活动期AS患者[实验组，男43例、女5例，年龄（26.2±5.2）岁，均为HLA-B27+]和49例健康志愿者[对照组，男44例、女5例，年龄（25.9±4.8）岁，HLA-B27+43例、HLA-B27-6例]。ELISA检测外周血清中IL-17A及IL-23水平，流式细胞术检测外周血单个核细胞（PBMCs）中的CCR4+CCR6+Th细胞（Th17）及Treg细胞数量。分离健康志愿者的PBMCs，将PBMCs分别与AS患者及健康志愿者的BMSCs体外共培养72 h，收集PBMCs行流式细胞术检测，评价BMSCs与Th17/Treg体外的相互作用。结果实验组与对照组血清IL-17A及IL-23的表达水平相近（P>0.05）；实验组Th17细胞明显高于对照组（P<0.05），而Treg细胞明显低于对照组（P<0.05）。与健康志愿者BMSCs共培养72 h后的PBMCs中Th17较培养前轻度下降，Treg轻度上升，差异无统计学意义（P>0.05）；而与AS患者BMSCs共培养72 h的PBMCs中Th17较培养前及对照组均明显上升，Treg均明显下降，差异均有统计学意义（P<0.05）。结论 AS患者PBMCs中Th17/Treg细胞亚群失衡。免疫抑制能力明显下降的BMSCs极可能通过诱导Th17/Treg失衡而在AS免疫发生机制中发挥重要作用。