Glycoprotein Ib

Glycoprotein Ib, abbreviated to GPIb is a component of the GPIb-V-IX complex on platelets. It is deficient in the Bernard-Soulier syndrome. A gain-of-function mutation causes platelet-type von Willebrand's disease

It is also known as "CD42".

Autoantibodies against Ib/IX can be produced in immune thrombocytopenic purpura.

Components include GP1BA and GP1BB.

It complexes with Glycoprotein IX.