Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Antigenic characterization of endothelial cell‐derived microparticles and their detection ex vivo

Antigenic characterization of endothelial cell‐derived microparticles and their detection ex vivo Summary. Background: Endothelial activation and dysfunction are associated with several diseases. However, hardly any specific markers are available. Microparticles (MP) from endothelial cells (EC; EMP) were reported in patient groups and healthy individuals. The antibodies used to detect EMP, however, were mainly directed against antigens without EC specificity. Objectives: We evaluated the antigens on EC and EMP to establish proper markers for EMP detection. Methods: EMP were isolated from supernatants of resting and interleukin (IL)‐1α activated human umbilical vein EC (HUVEC; n = 3; 0–72 h), stained with annexin V and monoclonal antibodies, and analyzed by flow cytometry. Human platelet‐MP (PMP), the main MP population in plasma, were prepared in vitro. EMP and PMP were studied in plasma from systemic lupus erythematosus (SLE) patients (n = 11) and healthy individuals (n = 10). Results: Platelet–endothelial cell adhesion molecule‐1 (PECAM‐1), αν and β3 were constitutively exposed on HUVEC, but (almost) absent on EMP (<15% positive for αν and β3), or only exposed on a subpopulation (PECAM‐1; 30–60%). Activated HUVEC (>80%) and (subpopulations of) EMP exposed E‐selectin and tissue factor. PMP strongly exposed PECAM‐1, β3, and glycoprotein (GP)Ib (CD42b), but not αν or E‐selectin. GPIb and P‐selectin (CD62P) were absent on EMP. Plasma samples contained 0.5% MP staining for E‐selectin and/or αν. Plasma from one SLE patient contained E‐selectin exposing MP (21%), but little αν‐positive MP. Conclusions: EC release EMP in vitro. The antigenic phenotype of EMP released from resting and IL‐1α‐stimulated EC differs among each other as well as from resting and stimulated EC, respectively. E‐selectin exposed on IL‐1α‐stimulated EC is a valid marker for EMP detection ex vivo to establish endothelial cell activation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Thrombosis and Haemostasis Wiley

Antigenic characterization of endothelial cell‐derived microparticles and their detection ex vivo

Download PDF
10 pages

Loading next page...
 
/lp/wiley/antigenic-characterization-of-endothelial-cell-derived-microparticles-nb19okJbj3

References (35)

Publisher
Wiley
Copyright
Copyright © 2003 Wiley Subscription Services, Inc., A Wiley Company
ISSN
1538-7933
eISSN
1538-7836
DOI
10.1046/j.1538-7836.2003.00455.x
Publisher site
See Article on Publisher Site

Abstract

Summary. Background: Endothelial activation and dysfunction are associated with several diseases. However, hardly any specific markers are available. Microparticles (MP) from endothelial cells (EC; EMP) were reported in patient groups and healthy individuals. The antibodies used to detect EMP, however, were mainly directed against antigens without EC specificity. Objectives: We evaluated the antigens on EC and EMP to establish proper markers for EMP detection. Methods: EMP were isolated from supernatants of resting and interleukin (IL)‐1α activated human umbilical vein EC (HUVEC; n = 3; 0–72 h), stained with annexin V and monoclonal antibodies, and analyzed by flow cytometry. Human platelet‐MP (PMP), the main MP population in plasma, were prepared in vitro. EMP and PMP were studied in plasma from systemic lupus erythematosus (SLE) patients (n = 11) and healthy individuals (n = 10). Results: Platelet–endothelial cell adhesion molecule‐1 (PECAM‐1), αν and β3 were constitutively exposed on HUVEC, but (almost) absent on EMP (<15% positive for αν and β3), or only exposed on a subpopulation (PECAM‐1; 30–60%). Activated HUVEC (>80%) and (subpopulations of) EMP exposed E‐selectin and tissue factor. PMP strongly exposed PECAM‐1, β3, and glycoprotein (GP)Ib (CD42b), but not αν or E‐selectin. GPIb and P‐selectin (CD62P) were absent on EMP. Plasma samples contained 0.5% MP staining for E‐selectin and/or αν. Plasma from one SLE patient contained E‐selectin exposing MP (21%), but little αν‐positive MP. Conclusions: EC release EMP in vitro. The antigenic phenotype of EMP released from resting and IL‐1α‐stimulated EC differs among each other as well as from resting and stimulated EC, respectively. E‐selectin exposed on IL‐1α‐stimulated EC is a valid marker for EMP detection ex vivo to establish endothelial cell activation.

Journal

Journal of Thrombosis and Haemostasis – Wiley

Published: Nov 1, 2003

There are no references for this article.