Tissue metalloproteinase inhibitor 3 (TIMP-3) is a protein encoded by the TIMP3 gene and belongs to the tissue inhibitor family of metalloproteinase genes. There are four members of the family: TIMP-1, TIMP-2, TIMP-3 and TIMP-4. TIMP-3 is a 30 kDa glycoprotein secreted by many types of cells. TIMP-3 inhibits active MMP-mediated proteolysis by forming a non-covalent binary complex with the MMP active site through its N-terminal domain. In addition, TIMP-3 is also an inflammatory factor inhibitor, which negatively regulates TACE and promotes the release of TNF-α, which in turn causes inflammation and vascular remodeling in the body. This gene mutation is associated with autosomal dominant Sorsby fundus dystrophy.