Macrophage migration inhibitory factor (MIF) is an important regulator of innate immunity. Bacterial antigens stimulate white blood cells to release MIF into the bloodstream. Circulating MIF binds to CD74 on other immune cells to trigger an acute immune response, so MIF is an inflammatory cytokine. In addition, glucocorticoids can also stimulate white blood cells to release MIF. MIF regulates the function of macrophages in host defense by inhibiting the anti-inflammatory effects of glucocorticoids. MIF is an inflammatory mediator associated with the severity of rheumatoid arthritis. Plasma levels of MIF protein are elevated in people with schizophrenia, including in the early stages of the disease, but the clinical significance of this phenomenon has not been established. MIF also induces cardiac changes during sepsis. In addition, there is evidence that there is an association between MIF production and the metastatic potential of colon cancer.