Tissue inhibitors of metalloproteinases or TIMPs are a family of proteins that regulate the activation and proteolytic activity of the zinc enzymes known as matrix metalloproteinases (MMPs). There are four members of the family,TIMP-1,TIMP-2,TIMP-3,and TIMP-4. Tissue Inhibitor of Metalloproteinases 2 (TIMP-2) is a non N-glycosylated protein with a molecular mass of 22 kDa. It produced by a wide range of cell types,which inhibits MMPs non-covalently by the formation of binary complexes and irreversibly inactivates them by binding to their catalytic zinc cofactor. TIMP-2 also has erythroid-potentiating and cell growth promoting activities.