寻常型银屑病患者外周血Th17/Treg细胞免疫失衡的研究

Study on imbalance of the peripheral blood Th17/Treg cells in patients with psoriasis vulgaris

目的探讨寻常型银屑病患者外周血Th17细胞与Treg细胞的数量以及相关细胞因子的表达水平,分析Th17/Treg细胞免疫失衡在银屑病发病机制中的作用及与疾病严重程度的相关性,进一步阐述银屑病的发病机制。方法选取92例寻常型银屑病患者作为试验组,同时选60例健康查体者作为正常对照组,采用流式细胞术检测患者及正常人外周血Th17细胞和Treg细胞比例,采用ELISA法检测患者及正常人血清中IL-17、IL-23、TGF-β的含量,同时以皮损面积和严重程度(PASI)评分评价银屑病病情的严重程度。结果寻常型银屑病患者外周血Th17百分比、IL-17和IL-23水平均明显高于正常对照组,差异有统计学意义(P值均<0.01),Th17/Treg比值和IL-17/TGF-β比值也明显高于正常对照组,差异有统计学意义(P<0.01);而银屑病患者外周血Treg百分比及血清中TGF-β水平显著低于正常对照组,差异有统计学意义(P<0.01)。进行期Th17/Treg比值高于稳定期,Treg百分比低于稳定期,差异有统计学意义(P<0.01)。银屑病患者Th17细胞百分比、Th17/Treg比值、IL-17/TGF-β比值、IL-17和IL-23水平与PASI评分呈显著正相关(P<0.01),而Treg细胞百分比、TGF-β水平与PASI评分呈显著负相关(P<0.01)。Th17细胞、Treg细胞、Th17/Treg比值、IL-17/TGF-β比值、IL-17、IL-23和TGF-β与病程均无相关性(P>0.05)。结论 Th17/Treg细胞免疫失衡可能在寻常型银屑病的发病机制中发挥重要作用,可望通过调节患者外周血Th17/Treg细胞失衡及相关细胞因子而达到治疗银屑病的目的。

Objective To investigate the quantity of peripheral blood T helper 17（Th17）and CD4＋CD25＋regulatory T（Treg）cells and the expression of related cytokines in psoriasis vulgaris, and to analyze the role of Th17/Treg imbalance in the pathogenesis of psoriasis vulgaris. Methods Peripheral blood was obtained from 92 patients with psoriasis vulgaris and 60 normal human controls. Flow cytometry was performed to determine the percentage of Th17 and Treg cell in peripheral blood. Enzyme linked immunosorbent assay（ELISA）was used to measure the levels of IL-17, IL-23 and TGF-β. Psoriasis area and severity index（PASI）scores was used to assess the disease severity in patient with psoriasis vulgaris. Results Compared with normal human controls, patients with psoriasis vulgaris showed higher level of Th17 cells in peripheral blood （P〈0.01）. The serum levels of IL-17and IL-23 were significantly higher in patients with psoriasis. The ratios of Th17 to Treg cells and serum IL-17 to TGF-β were significantly higher in the patients than those in the normal controls （P〈0.01）, but the percentage of Treg cells and serum level of TGF-βwere significantly lower in the patients with psoriasis compared with the normal controls（P〈0.01）. The radios of Th17/Treg in the active stage was higher than that in stationary stage, the expression of Treg cells in the active stage was lower than that in stationary stage, the difference was statistically significant（P〈0.01）.The PASI score in patient was positively correlated with the percentage of Th17, Th17/Treg ratios and IL-17/TGF-β ratios, serum levels of IL-17 and IL-23, and negatively correlated with the percentage of Treg cells and serum level of TGF-β（P〈0.01）. The Th17/Treg and IL-17/TGF-βratios, the percentage of Th17 and Treg cells were unrelated to the clinical course of patients with psoriasis（P〉0.05）.The serum levels of IL-17, IL-23, TGF-βwere unrelated to the clinical course of patients with psoriasis too（P〉0.05）. Conclusion The imbalance between Th17 and Treg cells may play an important role in the pathogenesis of psoriasis. Regulating the imbalance of the Th17/Treg cells and related cytokines IL-17,IL-23, TGF-β may become a novel target for the treatment of psoriasis.