外周血CD19+B细胞PD-L1的表达与系统性红斑狼疮发病的相关性分析

目的:探讨程序性死亡配体1(Programmed death ligand-1,PD-L1)在系统性红斑狼疮(Systemic lupus erythema-tosus,SLE)患者外周血B细胞上的表达及临床意义。方法:应用流式细胞仪检测51例SLE患者和38例健康对照者外周血CD19+B细胞表面PD-L1的表达水平,比较SLE稳定组、活动组和健康对照组以及狼疮肾炎组和无狼疮肾炎组之间CD19+B细胞表面PD-L1表达阳性细胞的百分比,并分析其与临床表现及实验室检查数据的相关性。结果:SLE活动组和稳定组CD19+PD-L1+B细胞百分率均低于健康对照组,活动组又低于稳定组,差异均有统计学意义(均P<0.05)。狼疮肾炎患者CD19+PD-L1+B细胞百分率低于无狼疮肾炎患者(P<0.05)。SLE患者CD19+PD-L1+B细胞百分率与SLEDAI评分、尿蛋白定量、呈负相关,与C3呈正相关。SLE患者中抗dsDNA抗体、抗Sm抗体、抗U1snRNP抗体、抗核小体抗体阳性组外周血B细胞PD-L1表达水平均低于对应阴性组,且均有统计学意义(均P<0.05)。结论:SLE患者外周血CD19+B细胞表达PD-L1下降,与病情活动性和抗体产生有很好的相关性。

Reduced expression of PD-L1 on CD19~+ B cells from the peripheral blood of patients with systemic lupus erythematosus

Objective:To detect expression of PD-L1 on CD19+ B cells from patients with systemic lupus erythematosus(SLE) and analyze the clinical relevance to disease severity.Methods:The expression of PD-L1 on the CD19+ B cells was examined in 51 active SLE patients and 38 healthy controls(HC) by flow cytometry.The proportions of PD-L1 positive CD19+ B cells were compared between not only inactive or active SLE patients and healthy controls(HC),but also between patients with and without lupus nephritis.Correlations with clinical manifestations and laboratory findings was analyzed.Results:The Proportions of CD19+PD-L1+ B cells were significantly decreased in active and inactive SLE patients as compared with HC(all P<0.05).The number of CD19+PD-L1+ B cells in SLE patients with nephritis were significantly lower than those in patients without nephritis.A negative correlation was observed for proportions of CD19+PD-L1+B cells with SLEDAI score and amounts of proteinuria.But positively correlated with C3.Reduced numbers of CD19+PD-L1+B cells in SLE patients were also correlated to increased level of anti-dsDNA,anti-Sm,anti-U1snRNP and anti-Nucleosome antibodies in SLE patients(all P<0.05).Conclusion:The aberrations of CD19+PD-L1+ B cells were observed in patients with SLE.Reduced numbers of CD19+PD-L1+B cells were correlated with increased disease activity and the production of anti-self antibodies.