Thromb Haemost 1981; 46(02): 504-506
DOI: 10.1055/s-0038-1653397
Original Article
Schattauer GmbH Stuttgart

Antithrombin III, the Major Modulator of Intravascular Coagulation, Is Synthesized by Human Endothelial Cells

T K Chan
The Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong
,
Vivian Chan
The Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong
› Author Affiliations
Further Information

Publication History

Received 20 March 1981

Accepted 04 May 1981

Publication Date:
05 July 2018 (online)

Preview

Summary

Human endothelial cells in culture is shown to synthesize antithrombin III (At-III). The endothelial cell At-III(EC-At-III) consists of a small fraction similar to plasma At-III and a larger fraction with decreased heparin-binding as tested by crossed immunoelectrophoresis. However, both the anti-Xa and thrombin-neutralizing activities of the EC-At-III were rapid and active even in the absence of added heparin. It is concluded that the major portion was probably bound to endogenous heparin-like substance, thus accounting for its decreased exogenous heparin binding. The presence of At-III and other antithrombotic factors in the vascular endothelium offer protection against thrombosis and possibly atherosclerosis.