von Willebrand factor (vWf) is known to interact with the two β3 integrins, α(IIb)β3 and α(v)β3, in an RGD-dependent manner. We characterized a novel murine monoclonal antibody to human vWf, GUR76-23, which recognized a site within the carboxy-terminal half of the molecule containing the RGD sequence. This antibody inhibited high shear-induced platelet aggregation and blocked adhesion of ADP plus epinephrine-stimulated platelets to vWf, indicating that it interferes with the interaction with α(IIb)β3. Unlike antibodies against the RGD site, however, the antibody was without effect on adhesion of cultured human umbilical vein endothelial cells to vWf, a phenomenon known to involve the interaction with α(v)β3. GUR76-23 binding was not displaced by anti-RGD antibodies. These results suggest that the adhesive interaction of vWf with these two β3 integrins may be differentially modulated by a site(s) other than the common RGD module.
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - 1997 May 8|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology