A patient with platelets deficient in glycoprotein VI that lack both collagen-induced aggregation and adhesion.
J Clin Invest
; 84(5): 1440-5, 1989 Nov.
Article
em En
| MEDLINE
| ID: mdl-2808700
ABSTRACT
Molecular level studies on platelets deficient in collagen-induced aggregation provide evidence for identifying possible platelet collagen receptors. We investigated platelets from a patient with mild bleeding time prolongation, but otherwise normal coagulation data. Her platelets lacked collagen-induced aggregation and adhesion, but retained normal aggregation and release by other agonists. Labeling her platelets with 125I or 3H and analysis by SDS-PAGE/autoradiography showed normal levels of glycoproteins Ia, Ib, IIa, IIb, IIIa, and IV. However, there were significantly decreased incorporations of both radioactivities into a 61-kD membrane glycoprotein (GP), which was identified as GPVI from its mobility on unreduced-reduced, two-dimensional SDS-PAGE. Sugiyama et al. (1987. Blood. 69 1712) reported that the serum from an idiopathic thrombocytopenic purpura (ITP) patient contained an antibody against a 62-kD platelet protein. Our patient's platelets lacked the antigen for the ITP patient's antibody, demonstrating that the ITP serum contains a specific antibody against GPVI. The patient's parents' platelets contained approximately 50% the normal amount of GPVI, but still had normal collagen-induced aggregation and adhesion. The patient's platelets did not bind to types I and III collagen fibrils. Our results suggest that GPVI functions as a collagen receptor.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plaquetas
/
Glicoproteínas da Membrana de Plaquetas
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Adesividade Plaquetária
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Agregação Plaquetária
/
Colágeno
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
Idioma:
En
Ano de publicação:
1989
Tipo de documento:
Article