Cartilage oligomeric matrix protein (COMP) is also known as Thrombospondin5 (TSP5), EDM1, EPD1, MED, PSACH, THBS5, which belongs to the thrombospondin family. COMP / TSP5 contains 4 EGFlike domains, 1 TSP Cterminal (TSPC) domain, 8 TSP type3 repeats. Abundantly expressed in the chondrocyte extracellular matrix, and is also found in bone, tendon, ligament and synovium and blood vessels. COMP may play a role in the structural integrity of cartilage via its interaction with other extracellular matrix proteins such as the collagens and fibronectin. COMP can mediate the interaction of chondrocytes with the cartilage extracellular matrix through interaction with cell surface integrin receptors. Thrombospondin5 could play a role in the pathogenesis of osteoarthritis. COMP is a marker of cartilage turnover. - Proteine/Peptide