Acquired deficiencies of protein S. Protein S activity during oral anticoagulation, in liver disease, and in disseminated intravascular coagulation.
Open Access
- 1 May 1988
- journal article
- Published by American Society for Clinical Investigation in JCI Insight
- Vol. 81 (5), 1445-1454
- https://doi.org/10.1172/jci113475
Abstract
Protein S is a vitamin K-dependent plasma protein which serves as the cofactor for activated protein C. Protein S circulates in both an active, free form and in an inactive complex with C4b-binding protein. To elucidate the role of protein S in disease states and during oral anticoagulation, we developed a functional assay for protein S that permits evaluation of the distribution of protein S between free and bound forms and permits determination of the specific activity of the free protein S. In liver disease, free protein S antigen is moderately reduced and the free protein S has significantly reduced specific activity. In disseminated intravascular coagulation, reduced protein S activity occurs due to a redistribution of protein S to the inactive bound form. During warfarin anticoagulation, reduction of free protein S antigen and the appearance of forms with abnormal electrophoretic mobility significantly decrease protein S activity. After the initiation of warfarin, the apparent half-life of protein S is 42.5 h. In patients with thromboembolic disease, transient protein S deficiency occurs due to redistribution to the complexed form. Caution should be exercised in diagnosing protein S deficiency in such patients by use of functional assays.Keywords
This publication has 25 references indexed in Scilit:
- Oral contraceptives and gender affect protein S status.1987
- Plasma protein S deficiency in familial thrombotic disease.1984
- Comparison of coagulation factor Xa and des-(1-44)factor Xa in the assembly of prothrombinase.Journal of Biological Chemistry, 1984
- Purification of human C4b-binding protein and formation of its complex with vitamin K-dependent protein SBiochemical Journal, 1983
- Isolation of a membrane-bound cofactor for thrombin-catalyzed activation of protein C.Journal of Biological Chemistry, 1982
- Regulation of activated protein C by protein S. The role of phospholipid in factor Va inactivation.Journal of Biological Chemistry, 1981
- Regulation of activated protein C by a new protein. A possible function for bovine protein S.Journal of Biological Chemistry, 1980
- Modulation of the classical pathway C3 convertase by plasma proteins C4 binding protein and C3b inactivator.Proceedings of the National Academy of Sciences of the United States of America, 1979
- Quantitative Estimation of Coagulation Factors in Liver Disease. The Diagnostic and Prognostic Value of Factor XIII, Factor V and PlasminogenThrombosis and Haemostasis, 1978
- The conversion of prothrombin to thrombin. I. Characterization of the reaction products formed during the activation of bovine prothrombin.1974