Pathophysiology
Glycoprotein IIb/IIIa (GpIIb/IIIa), also known as αIIbβ3, is an integrin aggregation receptor on platelets. This receptor is activated when the platelet is stimulated by ADP, epinephrine, collagen, or thrombin. GpIIb/IIIa is essential to blood coagulation since the activated receptor has the ability to bind fibrinogen (as well as von Willebrand factor, fibronectin, and vitronectin), which is required for fibrinogen-dependent platelet-platelet interaction (aggregation.)
In contrast, Glanzmann's thrombasthenia has normal glycoprotein Ib receptors, the role of which is to enable platelet activation by contact with the von Willebrand factor-collagen complex that is exposed when the endothelial blood vessel lining is damaged.
Understanding of the role of GpIIb/IIIa in Glanzmann's thrombasthenia led to the development of GpIIb/IIIa inhibitors, a class of powerful antiplatelet agents.
Read more about this topic: Glanzmann's Thrombasthenia