A monoclonal antibody directed against human von Willebrand factor induces type 2B-like alterations.
J Thromb Haemost
; 2(9): 1622-8, 2004 Sep.
Article
en En
| MEDLINE
| ID: mdl-15333040
ABSTRACT
We have previously described a monoclonal antibody (mAb), 1C1E7, against von Willebrand factor (VWF), that increases ristocetin-induced platelet aggregation (RIPA) and induces a preferential binding of the high-molecular-weight multimers of VWF to platelet GPIb. Further investigations using a rotational viscometer at a shear rate of 4000 s(-1) could now demonstrate that shear-induced platelet aggregation (SIPA) is significantly increased with 1C1E7 and that this could be completely inhibited by the anti-GPIb mAb 6D1. In contrast, platelet adhesion to a collagen surface at a shear rate of 2600 s(-1), using a rectangular perfusion chamber, was significantly inhibited in the presence of 1C1E7. When citrated whole blood was incubated with 1C1E7, a spontaneous binding of VWF to the platelet GPIb could be demonstrated by flow cytometric analysis. Parallel to this, a decrease of the highest molecular weight multimers of VWF in the plasma was found. Platelets with bound VWF on their surface were able to form macroaggregates but were no longer able to adhere. These phenomena are very similar to the alterations described in von Willebrand's disease type 2B. The epitope of this mAb could be localized to the N-terminal part of the subunit; therefore a distant conformational change in the A1 domain of VWF is suggested.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Factor de von Willebrand
/
Anticuerpos Monoclonales
Límite:
Humans
Idioma:
En
Revista:
J Thromb Haemost
Asunto de la revista:
HEMATOLOGIA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Bélgica