title: Platelet-based coagulation: different populations, different functions.
abstract: Platelets in a thrombus interact with (anti)coagulation factors and support blood coagulation. In the concept of cell-based control of coagulation, three different roles of platelets can be distinguished: control of thrombin generation, support of fibrin formation, and regulation of fibrin clot retraction. Here, we postulate that different populations of platelets with distinct surface properties are involved in these coagulant functions. Platelets with elevated Ca(2+) and exposed phosphatidylserine control thrombin and fibrin generation, while platelets with activated α(IIb) β(3) regulate clot retraction. We review how coagulation factor binding depends on the platelet activation state. Furthermore, we discuss the ligands, platelet receptors and downstream intracellular signaling pathways implicated in these coagulant functions. These insights lead to an adapted model of platelet-based coagulation.
authors.affiliation: Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands. jwm.heemskerk@maastrichtuniversity.nl
authors.forename: J W M
authors.initials: JW
authors.lastname: Heemskerk
authors.forename: N J A
authors.initials: NJ
authors.lastname: Mattheij
authors.forename: J M E M
authors.initials: JM
authors.lastname: Cosemans
mesh_terms: D000818:Animals; D001777:Blood Coagulation; D001792:Blood Platelets / Q000145:classification / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D003018:Clot Retraction; D005337:Fibrin / Q000378:metabolism; D006801:Humans; D010718:Phosphatidylserines / Q000097:blood; D015539:Platelet Activation; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000378:metabolism; D015398:Signal Transduction; D013917:Thrombin / Q000378:metabolism; D013927:Thrombosis / Q000097:blood*
chemical_list: D010718:Phosphatidylserines; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D005337:Fibrin; D013917:Thrombin; D002118:Calcium