Macrophage migration inhibitory factor (MIF)

Abstract

Macrophage migration inhibitory factor (MIF) was originally described as the first T-cell derived cytokine, which inhibits the migration of macrophages from capillaries.1,2 Subsequently, after cloning in 1989,3 it was discovered to be expressed in most tissues, suggesting that it has a widespread role beyond the immune system.4 MIF has unusual biological properties. First, it is a pleiotropic factor with pro-inflammatory, hormonal, and enzymatic activities.5,6 Second, MIF is able to counter-regulate the immunosuppressive and anti-inflammatory effects of glucocorticoid (GC).7-11 Finally, MIF was reported to be induced by low concentrations of GC in a murine cell line,7 which is unusual for a proinflammatory cytokine. However, this observation has proved controversial with a recent report not supporting this in the same murine cell line. MIF was found to be suppressed with high concentrations of GCs, with no induction at low concentrations in two different cell lines.12.