The factor VIII C1 domain contributes to platelet binding.

ABSTRACT: Activated factor VIII (FVIIIa) forms a procoagulant complex with factor IXa on negatively charged membranes, including activated platelet surfaces. Membrane attachment involves the FVIII C2 domain; involvement of the adjacent C1 domain has not been established. Binding of recombinant FVIII C1C2 and C2 proteins to platelets was detected by flow cytometry using (1) anti-C2 monoclonal antibody ESH8 followed by a phycoerythrin-labeled secondary antibody; (2) biotinylated C1C2 detected by phycoerythrin-labeled streptavidin, and (3) C1C2 and C2 site-specifically labeled with fluorescein. Highest binding and lowest background were obtained using fluorescein-conjugated proteins. More than 90% of activated platelets bound C1C2, compared with approximately 50% for equimolar C2. Estimates using fluor

SUBMITTER: Hsu TC 

PROVIDER: S-EPMC2200805 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature