外周血循环滤泡辅助性T细胞及IL-21在银屑病中的表达及意义

摘要

Objective:To explore the frequency of circulating follicular helper T (Tfh) cells,level of related cytokine IL-21 and their clinical relevance in patients with psoriasis.Methods:38 psoriasis patients and 32 healthy controls were enrolled.Next to CD4+CXCR5+Tfh,CD4+CXCR5+ICOS+Tfh and Th17 were determined via flow cytometry.The levels of the serum IL-21 were measured by ELISA.The relationship between the levels of Tfh , Th17, IL-21 and psoriasis area and severity index ( PASI ) were analysed.Results:The frequency of CD4+CXCR5+Tfh,CD4+CXCR5+ICOS+Tfh,Th17 and IL-21 concentration in the peripheral blood were all significantly increased in psoriasis patients as compared to in controls ( P<0.05 ).Upregulation of IL-21 was associated with frequency of CD4+CXCR5+Tfh and CD4+CXCR5+ICOS+Tfh,while no correlation with Th17 was observed.Furthermore,CD4+CXCR5+ICOS+Tfh subset and IL-21 were positively correlated with PASI ,and nonsignificant correlation was found between CD 4+CXCR5+Tfh and PASI ( P>0.05 ).Conclusion: The levels of CD4+CXCR5+ICOS+Tfh cells and IL-21 were increased in the peripheral blood of patients with psoriasis ,and significantly correlated with disease severity ,indicating that Tfh cell subset might play an important role in the clinical progression of psoriasis.The correlations of Tfh , IL-21 and Th17 suggesting that Tfh cell subset may participate in pathogenesis of psoriasis through secreting IL-21,and the vast majority of IL-21-producing cells may be Tfh cells.%目的：探讨外周血循环滤泡辅助性T细胞（ Follicular helper T cells ，Tfh）及相关细胞因子IL-21在银屑病患者中的表达水平及其与疾病活动度的关系。方法：收集38例银屑病患者及32例健康对照者，流式细胞术检测外周血循环CD4＋CXCR5＋Tfh和CD4＋CXCR5＋ICOS＋Tfh细胞比例以及Th17细胞比例；ELISA检测血清IL-21浓度；分析这些指标间及与银屑病疾病活动度评分PASI间的相关性。结果：与健康对照者相比，银屑病患者外周血循环CD4＋CXCR5＋Tfh和CD4＋CXCR5＋ICOS＋Tfh细胞比例更高，血清IL-21浓度和Th17细胞比例亦显著高于对照组（ P＜0.05）；IL-21浓度与CD4＋CXCR5＋Tfh和CD4＋CXCR5＋ICOS＋Tfh细胞比例均显著正相关，而与Th17细胞比例间无显著相关性（ P＞0.05）；且CD4＋CXCR5＋ICOS＋Tfh细胞比例和血清IL-21与银屑病疾病活动度PASI评分显著正相关，而CD4＋CXCR5＋Tfh则与之无显著相关性（ P＞0.05）。结论：银屑病患者外周血循环Tfh比例、IL-21浓度上调与银屑病患者疾病活动度密切相关，提示Tfh可能参与银屑病的发生发展过程，这一效应可能是通过分泌高水平IL-21实现；IL-21浓度与Tfh细胞比例相关，而与Th17细胞比例无相关性提示银屑病患者IL-21可能主要由Tfh细胞分泌。