 The gene transfer options being studied include naked DNA, viral gene transfer vectors encoding Von Willebrand factor transgenes, and ex vivo cell therapy. The latter involves transplantation of the patients own cells modified with a corrected copy of the defective gene. Human blood outgrowth endothelial cells BOEC display all the properties needed for successful ex vivo cell therapy. We plan to obtain blood samples from normal research subjects and patients with Von Willebrand Disease in order to isolate blood outgrowth endothelial cells BOEC from peripheral blood, and develop a ex vivo gene therapy for Von Willebrand Disease. 