Ristocetin-dependent, but not botrocetin-dependent, binding of von Willebrand factor to the platelet glycoprotein Ib-IX-V complex correlates with shear-dependent interactions
Jf. Dong et al., Ristocetin-dependent, but not botrocetin-dependent, binding of von Willebrand factor to the platelet glycoprotein Ib-IX-V complex correlates with shear-dependent interactions, BLOOD, 97(1), 2001, pp. 162-168
Under conditions of high shear stress, both hemostasis and thrombosis are i
nitiated by the interaction of the platelet membrane glycoprotein (GP) Ib-I
X-V complex with its adhesive ligand, von Willebrand factor (VWF), in the s
ubendothelial matrix or plasma. This interaction involves the Al domain of
vWF and the N-terminal extracellular region of GP Iba (His-1-Glu-282), and
it can also be induced under static conditions by the modulators ristocetin
and botrocetin, In this study, a panel of anti-vWF and anti-GP Ib alpha an
tibodies-previously characterized for their effects on ristocetin- and botr
ocetin-dependent vWF-GP Ib-IX-V interactions-was analyzed for their capacit
y to inhibit either the adhesion of Chinese hamster ovary cells expressing
recombinant GP Iba to surface-associated vWF under hydrodynamic flow or she
ar-stress-induced platelet aggregation. The combined results suggest that t
he shear-dependent interactions between vWF and GP Ib alpha closely correla
te with ristocetin-rather than botrocetin-dependent binding under static co
nditions and that certain anti-vWF monoclonal antibodies are able to select
ively inhibit sheer-dependent platelet aggregation. The combined results su
ggest that the shear-dependent interactions between vWF and GP Ib alpha clo
sely correlate with ristocetin-rather than botrocetin-dependent binding und
er static conditions and that certain anti-vWF monoclonal antibodies are ab
le to selectively inhibit sheer-dependent platelet aggregation. (C) 2001 by
The American Society of Hematology.