Objective: To investigate the clinical relevance of serum interleukin-2 receptor α (IL-2Rα) in patients with systemic lupus erythematosus (SLE).
Methods: One hundred and seven SLE patients and 39 healthy controls with comparable age and gender were recruited at Peking University People's Hospital from January 2019 to December 2020. Complete clinical data in 107 SLE patients at baseline and follow-up were collected. SLE disease activity index 2000 (SLEDAI-2K) was used to assess the disease activity of the SLE patients. The serum level of IL-2Rα in the SLE patients and healthy controls was measured using enzyme-linked immunosorbent assay (ELISA). The association between serum IL-2Rα and clinical and laboratory parameters was investigated. Mann-Whitney U test or t test, Chi-square test and Spearman correlation were used for statistical analysis.
Results: The serum IL-2Rα levels were significantly higher in the SLE patients [830.82 (104.2-8 940.48) ng/L], compared with those in the healthy controls [505.1 (78.65-1 711.52) ng/L] (P < 0.001). Association analysis showed that the increased serum IL-2Rα was positively associated with SLEDAI-2K scores and anti-nucleosome antibody (r=0.357, P < 0.001; r=0.25, P=0.027, respectively). Thirty-six of 107 (33.6%) SLE patients had lupus nephritis. Serum IL-2Rα levels were significantly higher in the patients accompanied with lupus nephritis [1 102.14 (126.52-8 940.48) ng/L] than in the patients without lupus nephritis [743.89 (104.19-4 872.06) ng/L] (P=0.032). The patients in the high IL-2Rα group had more lupus nephritis compared with those in the low IL-2Rα group (40.8% vs. 19.4%, P=0.031). Meanwhile, SLEDAI-2K scores were found significantly higher in the high IL-2Rα group than in the low IL-2Rα group [10 (3-21) vs. 7 (3-16), P=0.001]. With the improvement of disease activity in the SLE patients after conventional treatments, serum levels of IL-2Rα [1 119.1 (372.25-2 608.86) ng/L] in the week 12 decreased significantly compared with the baseline [1 556.73 (373.08-8 940.48) ng/L] (P=0.042).
Conclusion: Serum IL-2Rα may be used as a biomarker of disease activity in patients with SLE. There is certain correlation between serum IL-2Rα and renal involvement in SLE.
目的: 探究系统性红斑狼疮(systemic lupus erythematosus，SLE)患者血清中白细胞介素-2受体α(interleukin-2 receptor α，IL-2Rα)水平在临床中的意义。
方法: 收集2019年1月至2020年12月就诊于北京大学人民医院的107例SLE患者病历资料，依据SLE疾病活动度指数(SLE disease activity index 2000，SLEDAI-2K)评估患者的病情活动情况，并选取年龄、性别分别匹配的39例健康人作为健康对照。采用酶联免疫吸附法测定SLE患者组和健康对照组的血清IL-2Rα水平，比较其差异并分析SLE患者IL-2Rα水平与临床指标及实验室指标的相关性。采用t检验或Mann-Whitney U检验、χ2检验和Spearman秩相关性分析进行统计学分析。
结果: SLE患者血清IL-2Rα水平[830.82(104.2~8 940.48) ng/L]较健康对照组[505.1(78.65~1 711.52) ng/L]明显升高(P < 0.001)。相关性分析显示，血清IL-2Rα水平与SLEDAI-2K评分及抗核小体抗体滴度呈正相关(r=0.357，P < 0.001;r=0.25，P=0.027)。107例SLE患者中36例(33.6%)合并狼疮性肾炎，合并狼疮性肾炎的患者血清IL-2Rα水平[1 102.14(126.52~8 940.48) ng/L]较未合并狼疮性肾炎患者[743.89(104.19~4 872.06) ng/L]明显升高(P=0.032)。高IL-2Rα水平组合并狼疮性肾炎者(40.8%)较低水平组(19.4%)明显升高(P=0.031)，高IL-2Rα水平组SLEDAI-2K评分更高[10 (3~21) vs. 7 (3~16)，P=0.001]。SLE患者常规治疗12周后血清IL-2Rα水平[1 119.1(372.25~2 608.86) ng/L]随病情改善较基线时[1 556.73 (373.08~8 940.48) ng/L]明显下降(P=0.042)。
结论: 血清IL-2Rα可作为SLE病情活动评估指标，与肾脏受累有一定相关性。
Keywords: Lupus erythematosus, systemic; Lupus nephritis; Receptor, interleukin-2; T-lymphocytes.