von Willebrand factor – glycoprotein Ib interaction interface (VWF-GPIb interface)

The von Willebrand factor (VWF) – glycoprotein Ib (GPIb) interaction interface is a specialized protein-protein interaction essential for platelet adhesion at sites of vascular injury, especially under high-shear blood flow conditions (UniProt P04275). This interface is formed by the binding of the VWF A1 domain to the N-terminal domain of the GPIbα subunit within the platelet GPIb-IX-V receptor complex (PubMed: 12193610). In healthy individuals, this interaction is tightly regulated to prevent spontaneous thrombosis while ensuring rapid clot formation upon vessel damage. However, in diseases like acquired thrombotic thrombocytopenic purpura (aTTP), the lack of the protease ADAMTS13 leads to the persistence of ultra-large VWF multimers that spontaneously bind platelets via this interface, causing microvascular occlusion (Scully et al., NEJM 2019). Drugs like caplacizumab, a bivalent nanobody, specifically target the VWF A1 domain to block this interaction, thereby preventing microthrombi formation in TTP patients (FDA Label: Cablivi). Other agents, such as anfibatide, target the GPIb receptor side of the interface to achieve similar antithrombotic effects (PubMed: 26338172). While therapeutically potent, the primary safety concern associated with disrupting this interface is an increased risk of mucocutaneous bleeding, as it impairs the body's natural ability to initiate platelet plug formation (PubMed: 30625070).

Other names

VWF-GPIb axisVWF A1-GPIbα interactionvon Willebrand factor-platelet glycoprotein Ib complexVWF-GPIbα interface

Inhibition of the binding between the A1 domain of von Willebrand factor and the glycoprotein Ib-IX-V complex on platelets to prevent shear-induced platelet aggregation.