MIF

Macrophage Migration Inhibitory Factor (MIF) is a small secreted protein that can act as a pleiotropic pro-inflammatory cytokine as well as an enzyme. MIF pro-inflammatory activity can be initiated by signaling through CD74 and CD44, resulting in the secretion of TNF-α, IL-1, IL-6, IL-8, and various MMPs. The enzymatic activity of MIF is characterized by its ability to act as a tautomerase, capable of catalyzing the keto to enol isomerization of keto-phenylpyruvate and L-dopachrome. It appears as though MIF catalytic activity is dependent upon a trimeric configuration and a free N-terminal proline residue. Insect cell derived recombinant MIF is a 15 kDa protein containing 124 amino acid residues, including an N-terminal His-tag.