Vanarsa Kamala, Ye Yujin, Han Jie, Xie Chun, Mohan Chandra, Wu Tianfu
Arthritis Res Ther. 2012 Aug 7;14(4):R182. doi: 10.1186/ar4012.
In a recent screening to detect biomarkers in systemic lupus erythematosus (SLE), expression of the iron storage protein, ferritin, was increased. Given that proteins that regulate the storage, transfer and release of iron play an important role in inflammation, this study aims to determine the serum and urine levels of ferritin and of the iron transfer protein, transferrin, in lupus patients and to correlate these levels with disease activity, inflammatory cytokine levels and markers of anemia.
A protein array was utilized to measure ferritin expression in the urine and serum of SLE patients and healthy controls. To confirm these results as well as the role of the iron transfer pathway in SLE, ELISAs were performed to measure ferritin and transferrin levels in inactive or active SLE patients and healthy controls. The relationship between ferritin/transferrin levels and inflammatory markers and anemia was next analyzed.
Protein array results showed elevated ferritin levels in the serum and urine of lupus patients as compared to controls, which were further validated by ELISA. Increased ferritin levels correlated with measures of disease activity and anemia as well as inflammatory cytokine titers. Though active SLE patients had elevated urine transferrin, serum transferrin was reduced.
Urine ferritin and transferrin levels are elevated significantly in SLE patients and correlate with disease activity, bolstering previous reports. Most importantly, these changes correlated with the inflammatory state of the patients and anemia of chronic disease. Taken together, altered iron handling, inflammation and anemia of chronic disease constitute an ominous triad in SLE.
在最近一项用于检测系统性红斑狼疮（SLE）生物标志物的筛查中，铁储存蛋白铁调素的表达增加。鉴于调节铁储存、转运和释放的蛋白质在炎症中起重要作用，本研究旨在测定狼疮患者血清和尿液中铁调素及铁转运蛋白转铁蛋白的水平，并将这些水平与疾病活动度、炎性细胞因子水平及贫血标志物相关联。
利用蛋白质芯片检测SLE患者及健康对照者尿液和血清中铁调素的表达。为证实这些结果以及铁转运途径在SLE中的作用，采用酶联免疫吸附测定（ELISA）法检测非活动期或活动期SLE患者及健康对照者的铁调素和转铁蛋白水平。接下来分析铁调素/转铁蛋白水平与炎症标志物及贫血之间的关系。
蛋白质芯片结果显示，与对照组相比，狼疮患者血清和尿液中铁调素水平升高，ELISA进一步验证了这一结果。铁调素水平升高与疾病活动度、贫血指标以及炎性细胞因子滴度相关。虽然活动期SLE患者尿液中转铁蛋白升高，但血清转铁蛋白降低。
SLE患者尿液中铁调素和转铁蛋白水平显著升高，且与疾病活动度相关，支持既往报道。最重要的是，这些变化与患者的炎症状态及慢性病贫血相关。综上所述，铁代谢改变、炎症及慢性病贫血在SLE中构成一个不祥的三联征。
