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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A major source of Von Willebrand factor (vWF) –
assistant
The correct answer is  Circulating factor VIII has two components.

a)   Factor VIIIc (Procoagulant protein)

This is the smaller component
It is synthesized in the liver (main source) and kidney.
It is an intrinsic pathway component required for activation of factor X.

b)   Von Willebrand factor (vWF)

This is the larger component.
It is produced by endothelial cells (main source) and megakaryocytes.
It has two major functions -


Helps in platelets adhesion by interacting platelet membrane glycoprotein Ib-IX.
Stabilizes factor VIIIc.