Macrophage migration inhibitory factor may contribute to vasculopathy in systemic sclerosis

Increasing evidence supports the concept of macrophage migration inhibitory factor (MIF) as a central proinflammatory cytokine in autoimmune diseases. To further evaluate its role in systemic sclerosis (SSc), serum levels of MIF were determined by enzyme-linked immunoassay, and correlations to clinical manifestations were analyzed in 43 patients. MIF levels were significantly increased in patients (median, 18.8; range, <0.015-189 ng/ml) in comparison to healthy controls (n=43, 8.0, <0.015-36.5 ng/ml; P<0.0005). MIF values were higher in diffuse than in limited cutaneous SSc (P<0.005). Patients with pulmonary hypertension and recurrent digital ulcers showed higher MIF levels than patients without these manifestations (P<0.005). This association was also observed in limited cutaneous SSc. Sequential studies revealed decreased MIF levels after initiation of immunosuppressive therapy. MIF levels were not significantly different in patients with and without macrovascular disease of the peripheral arteries. The results suggest that MIF might contribute to inflammation and vasculopathy in SSc.