Radioimmunoassays for protein C and factor X. Plasma antigen levels in abnormal hemostatic states.

Abstract

Specific radioimmunoassays, sensitive to plasma levels of less than 1% of normal, were developed for protein C and Factor X. In 31 normal subjects, mean plasma antigen levels were as follows: protein C, 3.23 +/- 0.79 microgram/mL (2 SD); Factor X, 7.74 +/- 1.81 microgram/mL. In patient son chronic warfarin therapy, protein C and factor X were depressed equivalently: protein C, 42% +/- 20% (of a pooled plasma reference); Factor X, 44% +/- 24%. Protein C antigen fell much more rapidly than Factor X antigen when warfarin therapy was begun, creating an initial period of potential hypercoagulability. In patients with severe liver disease, mean protein C antigen (25% +/- 17%) was lower than Factor X antigen (51% +/- 29%). Protein C antigen levels did not appear to be a sensitive indicator of compensated intravascular coagulation or systemic fibrinolysis induced by infusion of streptokinase. Clinical implications of these findings are discussed.

• Authors: D J Epstein, P W Bergum, S P Bajaj, S I Rapaport
• Journal: American journal of clinical pathology (Am J Clin Pathol) Vol. 82 Issue 5 Pg. 573-81 (Nov 1984) ISSN: 0002-9173 [Print] England
• PMID: 6548600 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Blood Coagulation Factors
• Glycoproteins
• Protein C
• Warfarin
• Factor X
• Streptokinase

Topics

• Blood Coagulation Factors (analysis)
• Cross Reactions
• Disseminated Intravascular Coagulation (immunology)
• Factor X (analysis)
• Female
• Glycoproteins (analysis)
• Hematologic Diseases (immunology)
• Hemostasis
• Humans
• Kinetics
• Liver Diseases (immunology)
• Lupus Erythematosus, Systemic (immunology)
• Pregnancy
• Protein C
• Radioimmunoassay
• Streptokinase (pharmacology)
• Warfarin (pharmacology)