Objectives: This study investigated the levels of macrophage migration inhibitory factor (MIF) in adult-onset Still's disease (AOSD) and explored the role of this pro-inflammatory cytokine in the systemic inflammation of AOSD.
Design and methods: Serum MIF levels were measured by ELISA in patients with AOSD and controls. Intracellular MIF production by peripheral blood leukocytes was detected by three-color flow cytometry.
Results: Serum MIF levels were significantly increased in patients with AOSD. Serum MIF levels were significantly higher in AOSD patients with sore throat, myalgias, splenomegaly, or pleuritis, and were closely correlated with clinical disease severity and activity. Examined by flow cytometry, the intracellular MIF levels in monocytes and T-lymphocytes from AOSD patients were significantly higher than those from healthy subjects.
Conclusion: These data represent the first demonstration of increased MIF expression in AOSD, and suggest that MIF may be an important marker for disease evaluation and monitoring.