It has been shown that platelets from patients with platelet- type von Willebrand’s
disease (vWD) agglutinate upon the addition of human von Willebrand factor (vWF) in
the absence of ristocetin or botrocetin, suggesting that platelet membrane receptors
for human vWF is abnormal. The present work reports the platelet agglutinability on
stimulation with bovine vWF in platelet-type vWD. Platelets in patient platelet-rich
plasma or washed platelet suspensions and patient platelets treated with formalin
agglutinated in the presence of markedly lower concentrations of bovine vWF than those
required for normal platelets. This finding provides additional evidence that platelet-type
vWD platelets have abnormal expression of binding sites for vWF on their surface,
and supports that platelet receptors for bovine vWF are identical or very close to
those for human vWF.
Keywords
Platelet-type von Willebrand’s disease - von Willebrand factor - Bovine von Willebrand
factor - Platelet agglutination - Receptor
