Macrophage migration inhibitory factor-mediated mast cell extracellular traps induce inflammatory responses upon Fusobacterium nucleatum infection.

Mast cell extracellular traps (MCETs) released by mast cells contribute to host defense. In this study, we investigated the effects of MCETs released from mast cells after infection with a periodontal pathogen Fusobacterium nucleatum. We found that F. nucleatum induced MCET release from mast cells, and that MCETs expressed macrophage migration inhibitory factor (MIF). Notably, MIF bound to MCETs induced proinflammatory cytokine production by monocytic cells. These findings suggest that MIF expressed on MCETs, released from mast cells upon infection with F. nucleatum, promotes inflammatory responses that may be associated with the pathogenesis of periodontal disease.