Human macrophage migration inhibitory factor (MIF), also known as glycosylation-inhibiting factor (GIF), is a pro-inflammatory cytokine that is an important regulator of innate immunity. Signaling works through CD74 and CD44, resulting in the release of TNF-α, IL-1, IL-6, and IL-8. MIF plays a role in the regulation of macrophage function in host defense through the suppression of anti-inflammatory effects of glucocorticoids. Increased MIF production seems to be involved in rheumatoid arthritis, colorectal cancer, and Alzheimer disease. Human MIF is 90% identical to mouse MIF.