Thrombospondin: a modular adhesive glycoprotein of platelets and nucleated cells.

This is the authors' abstract. We don't add key points for this paper.

Platelet adhesion to the subendothelial matrix and the subsequent aggregation of the activated platelets is a special case of intercellular adhesion that is highly regulated and for which multiple, possibly redundant systems exist. The large adhesive such as fibrinogen, von Willebrand factor, and fibronectin and their receptors, which participate in platelet adhesion and aggregation, are not unique to platelets, and probably serve analogous functions in a variety of cell types and locations. Thrombospondin (TS)/the most abundant protein of platelet alpha-granules, has been recognized as a new member of this class of glycoproteins. Whereas other glycoproteins are contained within alpha-granules and secreted upon platelet activation, they also exist in plasma at high concentrations. Hence TS is the only member of the group that is unique to alpha-granules and whose expression in quantity at sites of platelet aggregation is absolutely dependent on