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PubMed · 3390605

Thrombospondin promotes platelet aggregation.

G P Tuszynski·V L Rothman·A Murphy·K Siegler·K A Knudsen
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Abstract

Thrombospondin (TSP), isolated from human platelets, promotes aggregation of both nonstimulated platelets and platelets stimulated with thrombin or ADP. The TSP-promoted aggregation is specific since a monoclonal antibody against TSP inhibits the effect of exogenously added TSP and inhibits thrombin-induced platelet aggregation in the absence of added TSP. Several lines of evidence suggest that TSP mediates its effect on aggregation of nonstimulated and stimulated platelets through different platelet-surface receptor systems. The TSP-promoted aggregation of nonstimulated platelets was inhibited by a monoclonal antibody to platelet glycoprotein IV (GPIV), but not by a monoclonal antibody to the fibrinogen receptor, GPIIb-IIIa. In contrast, the antibody to GPIIb-IIIa totally inhibited the TSP-potentiated aggregation of thrombin-stimulated platelets, whereas the antibody to GPIV has no effect. Thus, these studies suggest that TSP promotes platelet aggregation by at least two mechanisms--one dependent on and one independent of the platelet fibrinogen receptor system.

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Adenosine DiphosphateAntibodies, MonoclonalBlood PlateletsGlycoproteinsHumansPlatelet AggregationThrombinThrombospondinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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G P Tuszynski, V L Rothman, A Murphy, K Siegler, K A Knudsen. 1988. Thrombospondin promotes platelet aggregation.. https://pubmed.ncbi.nlm.nih.gov/3390605/

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