Macrophage inhibitory factor (MIF) gene polymorphisms are associated with disease susceptibility and with circulating MIF levels in active non‐segmental vitiligo in patients from western Mexico

BACKGROUND: The macrophage migration inhibiting factor (MIF) is a protein that promotes the activation of immune cells and the production of other proinflammatory cytokines such as TNF‐α, IL‐1β, and IFN‐γ, which have proposed to play an essential role in the pathogenesis of vitiligo. The study aimed to assess the association between MIF polymorphisms (−794 CATT(5‐8) and −173 G>C), MIF in situ expression, and MIF serum concentrations with susceptibility and disease activity in patients with non‐segmental vitiligo (NSV) from western Mexico. METHODS: The study included 111 patients with NSV and 201 control subjects. Genotyping was performed by conventional PCR (−794 CATT(5‐8)) and PCR‐RFLP (−173 G>C) methods. MIF mRNA expression was quantified by real‐time PCR and MIF serum concentrations were determined by ELISA kit. Histopathological samples were analyzed by automated immunohistochemistry. RESULTS: The MIF polymorphisms were associated with NSV susceptibility. Serum concentrations of MIF were higher in patients with active NSV and correlated negatively with the years of evolution. The depigmented skin from patients with active vitiligo showed a high expression of MIF. CONCLUSION: MIF polymorphisms increase the risk of NSV in the western Mexican population. The serum concentrations of MIF and in situ expression are associated with active NSV.