Serum levels of macrophage migration inhibitory factor are associated with rheumatoid arthritis course.

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease of unknown etiology. Many cytokines have been found to be associated with RA pathogenesis and among them is macrophage migration inhibitory factor (MIF). The aim of this study was to determine whether MIF serum levels are associated with RA course, clinical activity, and clinical biomarkers of the disease. MIF levels were determined in serum samples of 54 RA patients and 78 healthy subjects (HS) by enzyme-linked immunosorbent assay (ELISA). Disease activity was evaluated using the DAS28 score. Patients were subgrouped according to disease activity and years of evolution of disease. Statistical analysis was carried out by SPSS 10.0 and GraphPad Prism 5 software. RA patients presented increased levels of MIF as compared to HS. MIF levels were raised on early stages of RA and tend to decrease according to years of evolution. Moreover, MIF levels positively correlated with rheumatoid factor in RA patients and with C reactive protein in all individuals studied. Our findings suggest that MIF plays a role in early stages of RA.