OBJECTIVES Macrophage migration inhibitory factor (MIF) and D-dopachrome tautomerase (DDT), members of the same cytokine superfamily, are linked to the pathogenesis of a number of inflammatory diseases. The aim of this study was to investigate their clinical relevance in systemic sclerosis (SSc). METHODS Serum MIF and DDT were quantified in 105 SSc patients by ELISA and levels compared to healthy controls (HC) (47) and patients with systemic lupus erythematosus (SLE) (184). Clinical parameters included organ involvement, serum laboratory markers and results of pulmonary function tests, and overall disease activity assessed using the European Scleroderma Trials and Research group (EUSTAR) activity index. RESULTS There was no significant difference in serum DDT concentrations between patients with SSc and HC. However, serum MIF was significantly increased in SSc compared to both HC and SLE cohorts. Serum MIF was increased in SSc patients with low forced vital capacity (FVC) and was also associated with the use of angiotensin II receptor blockers and beta blockers in SSc, confirmed after adjusting for the presence of systemic hypertension and low FVC. Serum DDT was significantly higher in SSc patients with low FEV1 and negatively correlated with EUSTAR score, particularly in patients with limited disease. CONCLUSION Although not significantly linked to specific clinical parameters, serum MIF was significantly higher in SSc patients than in HC and SLE patients, suggesting a fundamental role for MIF in SSc. DDT, while closely related to MIF, did not show a similar expression profile, suggesting functional differences between these molecules.

中文翻译：

---

系统性硬化症血清巨噬细胞迁移抑制因子和D-多巴色素互变异构酶的分析。

目的 巨噬细胞迁移抑制因子 (MIF) 和 D-多巴色素互变异构酶 (DDT) 是同一细胞因子超家族的成员，与许多炎症性疾病的发病机制有关。本研究的目的是调查它们在系统性硬化症 (SSc) 中的临床相关性。方法 通过 ELISA 对 105 名 SSc 患者的血清 MIF 和 DDT 进行量化，并与健康对照 (HC) (47) 和系统性红斑狼疮 (SLE) (184) 患者进行比较。临床参数包括器官受累、血清实验室标志物和肺功能测试结果，以及使用欧洲硬皮病试验和研究组 (EUSTAR) 活动指数评估的总体疾病活动性。结果 SSc 和 HC 患者的血清 DDT 浓度无显着差异。然而，与 HC 和 SLE 队列相比，SSc 中的血清 MIF 显着增加。低用力肺活量 (FVC) 的 SSc 患者的血清 MIF 升高，并且还与 SSc 中血管紧张素 II 受体阻滞剂和 β 受体阻滞剂的使用有关，这在调整全身性高血压和低 FVC 的存在后得到证实。血清 DDT 在 FEV1 低的 SSc 患者中显着升高，并且与 EUSTAR 评分呈负相关，特别是在疾病有限的患者中。结论 尽管与特定临床参数没有显着关联，但 SSc 患者的血清 MIF 显着高于 HC 和 SLE 患者，这表明 MIF 在 SSc 中的基本作用。DDT 虽然与 MIF 密切相关，但没有显示出相似的表达谱，表明这些分子之间存在功能差异。