TSP1, also named as THBS1, THBS and TSP, is an adhesive glycoprotein that mediates cell-to-cell and cell-to-matrix interactions, and which can bind to fibrinogen, fibronectin, laminin, type V collagen and integrins alpha-V/beta-1, alpha-V/beta-3 and alpha-IIb/beta-3. TSP1 is a regulator of many biological processes including cell growth, adhesion, migration, platelet aggregation, and fibrin deposition and lysis. It interacts with a number of plasma proteins such as fibrinogen and plasminogen and co-polymerizes with fibrin in clot formation. TSP1 is a 420 kDa homotrimeric glycoprotein with disulfide-linked subunits of 180 kDa.