Effect of recombinant MIF on lung fibroblast proliferation and collagen synthesis in vitro

AIM: To investigate the influence and mechanism of recombinant macrophage migration inhibitory factor (rMIF) on fibroblasts. METHODS: MRC-5 fibroblasts were divided into two groups: the treated group was treated with rMIF (25-100 μg/L, 12 h, 24 h or 48 h) and the control was non-rMIF treatment. The activity of proliferation in both groups was investigated and compared by CCK-8 means. Synthesis of collagen in the culture supernatants was detected by the hydroxyproline. The expression of collagen type I mRNA was examined using RT-PCR analysis. The level of collagen type I protein induced by rMIF was quantified by Western blotting. RESULTS: The production of proliferation ratio of fibroblasts treated with 50 μg/L and 100 μg/L rMIF at 24 h or 48 h were increased obviously (P<0.05 or P<0.01). The collagen synthesis significantly increased after stimulation with 100 μg/L rMIF for 48 h (P<0.01). rMIF significantly increased the expression of collagen type I mRNA and protein in a dose dependent manner compared with control (P<0.05 or P<0.01). CONCLUSION: rMIF upregulates the proliferation of fibroblasts and has an effect on the production of collagen. These results suggest that MIF may play important roles in the pathogenesis of airway remodeling.