Inhibition of the von Willebrand factor(vWF)-binding site of GPIbα with Fab fragments of the antibody p0p/B inwild-type mice abrogated platelet tethering and adhesion in a model of mechanicallyinduced arterial thrombosis as well as in ischemic stroke, while unspecific Fabfragments had no effect [7]. The gene discussed is VWF; the disease is ischemic stroke.