UMMS Affiliation
Department of Pediatrics
Publication Date
1987-11-01
Document Type
Article
Subjects
Antibodies, Monoclonal; Antigen-Antibody Complex; Blood Platelets; Flow Cytometry; Humans; Kinetics; *Platelet Glycoprotein GPIb-IX Complex; Platelet Membrane Glycoproteins; Thrombin
Disciplines
Hematology | Pediatrics
Abstract
Platelet membrane glycoprotein Ib (GPIb) and the GPIIb-IIIa complex have central roles in the interaction of platelets with the plasma coagulation system, damaged vessel walls, and other platelets. We investigated the effects of thrombin on these glycoproteins. Monoclonal antibodies were used to assess platelet surface glycoproteins by flow cytometry, total platelet glycoprotein content by immunoassay, and glycoproteins released from platelets, also by immunoassay. Five new observations were made with regard to thrombin-induced changes in platelet membrane glycoproteins: (a) The marked decrease in platelet surface binding of antibodies directed at GPIb was not confined to antibodies directed at the von Willebrand factor binding site. (b) There was a marked decrease in platelet surface binding of an antibody directed at GPIX, with maintenance of the 1:1 ratio of platelet surface binding of antibodies directed at GPIb and GPIX. (c) Changes in platelet surface binding of antibodies were not restricted to a distinct subpopulation of platelets. (d) There was no associated platelet release of glycocalicin (a proteolytic fragment of GPIb). (e) There was no associated platelet release of the GPIIb-IIIa complex. These thrombin-induced changes may be important in modulating the reactivity of platelets with the damaged vessel wall and with each other.
Source
Blood. 1987 Nov;70(5):1673-8.
Journal/Book/Conference Title
Blood
Related Resources
PubMed ID
3663949
Repository Citation
Michelson, Alan D. and Barnard, Marc R., "Thrombin-induced changes in platelet membrane glycoproteins Ib, IX, and IIb-IIIa complex" (1987). Open Access Articles. 311.
https://escholarship.umassmed.edu/oapubs/311