What is the role of integrins in platelet aggregation?
The dominant integrin on the platelet surface, aIIbb3, mediates platelet aggregation through binding of plasma fibrinogen and serves as the principal receptor for platelet adhesion to the ECM in vivo [6].
What is platelet integrin?
Integrins are a family of transmembrane glycoprotein signaling receptors that can transmit bioinformation bidirectionally across the plasma membrane. Integrin αIIbβ3 is expressed at a high level in platelets and their progenitors, where it plays a central role in platelet functions, hemostasis, and arterial thrombosis.
What could cause activation of platelets?
Platelets are normally activated in the presence of tissue injury with endothelial disruption and loss of activation inhibitors, exposure of the von Willebrand factor that binds it’s receptor and slows circulating platelets, and release of ADP, thrombin, and TxA2 as well as binding of fibrinogen or collagen to αIIb/β3.
Do platelets have integrin?
Platelets contain five integrins, three beta1 integrins that mediate platelet adhesion to the matrix proteins collagen, fibronectin and laminin, and the beta3 integrins alphavbeta3 and alphaIIbbeta3 [2] [J Clin Invest, 2005; 115: 3363].
How does atherosclerosis affect platelet function?
Platelets do not adhere or activate to the intact, non-activated endothelium. However, inflammatory events such as those observed in the early stages of atherosclerosis lead to endothelial activation which, in turn, may stimulate platelet attachment.
What is platelet release reaction?
During circulation, platelets are reactive to various stimuli and release the materials stored in the specific granules. This ‘release reaction’ is an important step of primary haemostasis. Energy and messengers required for platelet reactivity are provided by mitochondria and the dense tubular system.
Is platelet activation good or bad?
Abstract. Abciximab is a murine/human chimeric monoclonal antibody directed against the GPIIb/IIIa antigen, present on the surface of activated platelets.
What activates platelets and how do they behave after activation?
Thrombin causes proteolytic cleavage of fibrinogen, induces platelet activation, and triggers a wide range of effects secondary to thrombosis; for example, vascular smooth muscle cell and fibroblast proliferation, monocyte chemotaxis, and neutrophil adhesion.
What do integrins do in inflammation?
Integrins regulate cellular growth, proliferation, migration, signaling, and cytokine activation and release and thereby play important roles in cell proliferation and migration, apoptosis, tissue repair, as well as in all processes critical to inflammation, infection, and angiogenesis.