Isolation of the thrombospondin membrane receptor. Academic Article uri icon

Overview

abstract

  • Thrombospondin (TSP), a 450-kD multifunctional glycoprotein with a broad tissue distribution, is secreted upon platelet stimulation, binds to the activated platelet surface, and supports platelet aggregation. We have identified and isolated an 88-kd membrane glycoprotein present in platelets, endothelial cells, monocytes, and a variety of human tumor cell lines that is the membrane binding site for TSP. Endogenous platelet TSP binding to thrombin- and ionophore-stimulated human platelets was inhibited in the presence of the monoclonal antibody OKM5. TSP binding to C32 melanoma cells and HT1080 fibrosarcoma cells was specific and also inhibitable with OKM5 Mab. Cell labeling followed by specific immunoprecipitation demonstrated biosynthesis of a single 88-kD glycoprotein. Binding of TSP to the isolated membrane protein was specific and saturable. These studies identify an 88-kD membrane glycoprotein that reacts with the monoclonal antibody, OKM5, and may function as the cellular TSP receptor.

publication date

  • April 1, 1987

Research

keywords

  • Glycoproteins
  • Receptors, Mitogen

Identity

PubMed Central ID

  • PMC424283

Scopus Document Identifier

  • 0023251127

Digital Object Identifier (DOI)

  • 10.1172/JCI112918

PubMed ID

  • 2435757

Additional Document Info

volume

  • 79

issue

  • 4