Department of Rheumatology and Clinical Immunology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Rheumatology (Oxford). 2020 Sep 1;59(9):2616-2624. doi: 10.1093/rheumatology/keaa114.
Incomplete SLE (iSLE) patients display symptoms typical for SLE but have insufficient criteria to fulfil the diagnosis. Biomarkers are needed to identify iSLE patients that will progress to SLE. IFN type I activation, B-cell-activating factor (BAFF) and B-cell subset distortions play an important role in the pathogenesis of SLE. The aim of this cross-sectional study was to investigate whether B-cell subsets are altered in iSLE patients, and whether these alterations correlate with IFN scores and BAFF levels.
iSLE patients (n = 34), SLE patients (n = 41) with quiescent disease (SLEDAI ≤4) and healthy controls (n = 22) were included. Proportions of B-cell subsets were measured with flow cytometry, IFN scores with RT-PCR and BAFF levels with ELISA.
Proportions of age-associated B-cells were elevated in iSLE patients compared with healthy controls and correlated with IgG levels. In iSLE patients, IFN scores and BAFF levels were significantly increased compared with healthy controls. Also, IFN scores correlated with proportions of switched memory B-cells, plasma cells and IgG levels, and correlated negatively with complement levels in iSLE patients.
In this cross-sectional study, distortions in B-cell subsets were observed in iSLE patients and were correlated with IFN scores and IgG levels. Since these factors play an important role in the pathogenesis of SLE, iSLE patients with these distortions, high IFN scores, and high levels of IgG and BAFF may be at risk for progression to SLE.
不完全性系统性红斑狼疮（iSLE）患者表现出典型的 SLE 症状，但不符合诊断标准。需要生物标志物来识别将进展为 SLE 的 iSLE 患者。Ⅰ型干扰素（IFN）激活、B 细胞激活因子（BAFF）和 B 细胞亚群紊乱在 SLE 的发病机制中起重要作用。本横断面研究旨在探讨 iSLE 患者的 B 细胞亚群是否发生改变，以及这些改变是否与 IFN 评分和 BAFF 水平相关。
纳入 34 例 iSLE 患者、41 例处于疾病静止期（SLEDAI≤4）的 SLE 患者和 22 名健康对照者。采用流式细胞术检测 B 细胞亚群比例，用 RT-PCR 检测 IFN 评分，用 ELISA 检测 BAFF 水平。
与健康对照者相比，iSLE 患者的年龄相关 B 细胞比例升高，与 IgG 水平相关。iSLE 患者的 IFN 评分和 BAFF 水平显著高于健康对照者。此外，iSLE 患者的 IFN 评分与转换记忆 B 细胞、浆细胞和 IgG 水平的比例呈正相关，与补体水平呈负相关。
在这项横断面研究中，iSLE 患者存在 B 细胞亚群紊乱，与 IFN 评分和 IgG 水平相关。由于这些因素在 SLE 的发病机制中起重要作用，因此具有这些改变、高 IFN 评分、高 IgG 和 BAFF 水平的 iSLE 患者可能有进展为 SLE 的风险。
