Scripps VIVO scripps research logo

  • Index
  • Log in
  • Home
  • People
  • Organizations
  • Research
  • Events
Search form
As of April 1st VIVO Scientific Profiles will no longer updated for faculty, and the link to VIVO will be removed from the library website. Faculty profile pages will continue to be updated via Interfolio. VIVO will continue being used behind the scenes to update graduate student profiles. Please contact helplib@scripps.edu if you have questions.
How to download citations from VIVO | Alternative profile options

Binding of tissue plasminogen activator to human monocytes and monocytoid cells

Academic Article
uri icon
  • Overview
  • Identity
  • Additional Document Info
  • View All
scroll to property group menus

Overview

authors

  • Felez, J.
  • Chanquia, C. J.
  • Levin, E. G.
  • Miles, Lindsey
  • Plow, E. F.

publication date

  • November 1991

journal

  • Blood  Journal

abstract

  • Monocytes and monocytoid cell lines previously have been shown to express receptors for plasminogen and urokinase (u-PA). In the present study, the monocytoid cell lines, U937 and THP-1, are shown to bind tissue plasminogen activator (t-PA) in a specific, saturable, and reversible manner. These cells bound t-PA with low affinity (kd = 0.67 to 0.97 mumol/L) and high capacity (0.71 to 3.3 x 10(6) receptors/cell). Human peripheral blood monocytes bound t-PA with a kd (0.9 mumol/L) similar to that of the monocytoid cells but with a lower capacity (0.17 x 10(6) sites/cell). These binding parameters also were similar to the low-affinity interaction of t-PA with endothelial cells as measured with the cells in suspension (kd = 0.73 mumol/L and 1.1 x 10(6) sites/cell). Lysine analogues and active or diisopropylfluorophosphate-inactivated u-PA inhibited t-PA binding to monocytes, monocytoid cells, and endothelial cells with similar IC50 (concentration producing 50% inhibition) values, suggesting that the same recognition specificity mediates t-PA binding to all of these cell types. The existence of a high-affinity binding site for t-PA on monocytoid cells was also explored in detail. Unlike endothelial cells where plasminogen activator inhibitor-1 has been implicated in mediating a high-affinity interaction of t-PA with the cells, no evidence for a role of this inhibitor in ligand binding to the monocytoid cells was found. Furthermore, using both high and low 125I-t-PA concentrations, competition analyses with lysine analogues or u-PA, or treatment of the cells with carboxypeptidase B, failed to indicate the presence of distinguishable classes of t-PA binding sites. In sum, low-affinity receptors for t-PA are expressed at high density on monocytes and monocytoid cells, identifying a new element in the fibrinolytic arsenal of these cells.

subject areas

  • Arginine
  • Binding Sites
  • Cell Line
  • Endothelium, Vascular
  • Erythrocytes
  • Humans
  • Isoflurophate
  • Kinetics
  • Lysine
  • Monocytes
  • Neutrophils
  • Recombinant Proteins
  • Tissue Plasminogen Activator
  • Umbilical Veins
  • Urokinase-Type Plasminogen Activator
scroll to property group menus

Identity

International Standard Serial Number (ISSN)

  • 0006-4971

PubMed ID

  • 1932747
scroll to property group menus

Additional Document Info

start page

  • 2318

end page

  • 2327

volume

  • 78

issue

  • 9

©2022 The Scripps Research Institute | Terms of Use | Powered by VIVO

  • About
  • Contact Us
  • Support