Macrophage migration inhibitory factor in the sera and at the colonic mucosa in patients with ulcerative colitis: clinical implications and pathogenic significance

Background Inflammatory cytokines produced by activated macrophages are implicated in the pathogenesis of ulcerative colitis (UC). With the theory that macrophage migration inhibitory factor (MIF) may have a role in the accumulation of macrophages, we studied MIF in UC. Materials and methods A total of 27 patients with UC, 14 patients with Crohn's diseases (CD), 11 patients with other forms of colitis and 26 normal controls were enrolled in the study. The levels of MIF in the sera and culture supernatant were measured by an enzyme-linked immunosorbent assay. MIF, macrophages and T cells were localized at the colonic mucosa by immunohistochemistry. Results The levels of MIF in the sera were significantly higher in UC than in normal controls (P < 0.05), in serum C-reactive protein (CRP) -positive cases with UC than in CRP-negative cases with UC (P < 0.05), and in patients with severe colitis with UC than in mild colitis with UC (P < 0.05). There was a positive relationship between serum MIF levels with the CRP levels and activities of colitis. However, the levels of MIF in patients with CD and other forms of colitis were not significantly different from their levels in normal controls and UC. Infiltrating cells at the colonic mucosa in UC and CD expressed MIF. Conclusions These data suggest a role of MIF in the pathogenesis of UC. MIF may be used as a marker of disease activity in UC and control of MIF production may have therapeutic implications.