Subscribe to RSS
DOI: 10.1055/s-0038-1650221
Quantification of Circulating Activated Protein C in Human Plasma by Immunoassays - Enzyme Levels are Proportional to Total Protein C Levels
Publication History
Received 21 June 1995
Accepted after resubmission 10 October 1995
Publication Date:
10 July 2018 (online)
Summary
We have developed a simple assay that measures the circulating activated protein C (APC) in plasma. The assay requires collection of duplicate blood samples, one in citrate plus heparin and the other in citrate plus inhibitors of the enzyme. In the heparin tube, APC reacts completely and irreversibly with its major plasma inhibitors, protein C inhibitor (PCI) and α1-antitrypsin (α1AT), and the complexes formed are measured by ELISAs. The amount of circulating APC is calculated from the difference between the total amount of complexed APC (sample in citrate plus heparin) and the amount of APC complexed in vivo (sample in citrate plus inhibitor). Over 95% of the APC added to blood collected with heparin was recovered in the assay. The assay can easily be performed in four hours, and had a detection limit of 0.1 ng/ml APC. The mean APC level in 18 protein C heterozygous members from seven kindreds was significantly lower (0.6 ± 0.3 ng/ml) than in 20 healthy controls (1.1 ± 0.3 ng/ml) (p <0.001), whereas the mean level in 10 non-affected members from the kindreds studied was 1.5 ± 0.3 ng/ml. In the group of 12 nonanticoagulated heterozygous protein C-deficient individuals, the three patients with a history of venous thrombosis had a mean APC level significantly lower than the nine asymptomatic members (p <0.01), both subgroups showing similar protein C levels. There was a significant correlation in all groups between the levels of APC and the levels of protein C antigen (r = 0.758, p <0.0001) and activity (r = 0.745, p <0.0001), which means that APC circulating levels are proportional to protein C levels and suggests that the protein C level is the limiting factor in the rate of protein C activation in vivo.
-
References
- 1 Kisiel W, Canfield WM, Ericsson LH, Davie EW. Anticoagulant properties of bovine plasma protein C following activation by thrombin. Biochemistry 1977; 16: 5824-5831
- 2 Fulcher CA, Gardiner JE, Griffin JH, Zimmerman TS. Proteolytic inactivation of human Factor VIII procoagulant protein by activated human protein C and its analogy with Factor V. Blood 1984; 63: 486-489
- 3 Griffin JH, Evatt B, Zimmerman TS, Kleiss AJ, Wideman C. Deficiency of protein C in congenital thrombotic disease. J Clin Invest 1981; 68: 1370-1373
- 4 Branson H, Katz J, Marble R, Griffin JH. Inherited protein C deficiency and a coumarin-responsive chronic relapsing purpura fulminans syndrome in a neonate. Lancet 1983; 2: 1165-1168
- 5 Estellés A, García-Plaza I, Dasí A, Aznar J, Duart M, Sanz G, Pérez-Reque-jo JL, España F, Jimenez C, Abeledo G. Severe inherited “homozygous” protein C deficiency in a newborn infant. Thromb Haemost 1984; 52: 53-56
- 6 Gruber A, Griffin JH, Harker LA, Hanson SR. Inhibition of platelet-dependent thrombus formation by human activated protein C in a primate model. Blood 1989; 3: 639-642
- 7 Wydro R, Oppenheimer C, Rodger R, Niemi S. Recombinant activated protein C prevents occlusion in an arterio-venous shunt. Fibrinolysis 1988 2. (Suppl 1) 4a (abstr)
- 8 Gruber A, Hanson SR, Kelly AB, Yan BS, Bang N, Griffin JH, Harker LA. Inhibition of thrombus formation by activated recombinant protein C in a primate model of arterial thrombosis. Circulation 1990; 82: 578-585
- 9 Taylor FB, Chang A, Esmon CT, D’Angelo A, Vigano-D’Angelo S, Blick KE. Protein C prevents the coagulopathic and lethal effects of escherichia coli infusion in the baboon. J Clin Invest 1987; 79: 918-925
- 10 Okajima K, Imamura H, Koga S, Inoue M, Takatsuki K, Aoki N. Treatment of patients with disseminated intravascular coagulation by protein C. Amer J Hematol 1990; 33: 277-278
- 11 Dreyfus M, Magny JF, Bridey F, Schwartz HP, Planché C, Dehan M, Tchemia G. Treatment of homozygous protein C deficiency and neonatal purpura fulminans with a purified protein C concentrate. N Engl J Med 1991; 325: 1565-1568
- 12 Bauer KA, Kass BL, Beeler DL, Rosenberg RD. Detection of protein C activation in humans. J Clin Invest 1984; 74: 2033-2041
- 13 Heeb MJ, Mosher D, Griffin JH. Activation and complexation of protein C and cleavage and decrease of protein S in plasma of patients with intravascular coagulation. Blood 1989; 73: 455-461
- 14 Heeb MJ, España F, Griffin JH. Inhibition and complexation of activated protein C by two major inhibitors in plasma. Blood 1989; 73: 446-454
- 15 España F, Vicente V, Tabernero D, Scharrer I, Griffin JH. Determination of plasma protein C inhibitor and of two activated protein C-inhibitor complexes in normals and in patients with intravascular coagulation and thrombotic disease. Thromb Res 1990; 59: 593-608
- 16 Gruber A, Griffin JH. Direct detection of activated protein C in blood from human subjects. Blood 1992; 79: 2340-2348
- 17 Orthner CL, Kolen B, Drohan WN. A sensitive and facile assay for the measurement of activated protein C activity levels in vivo. Thromb Haemost 1993; 69: 441-447
- 18 España F, Berrettini M, Griffin JH. Purification and characterization of plasma protein C inhibitor. Thromb Res 1989; 55: 369-384
- 19 España F, Griffin JH. Determination of functional and antigen protein C inhibitor and its complexes with activated protein C in plasma by ELISA’s. Thromb Res 1989; 55: 671-682
- 20 Hendl S, España F, Aznar J, Estellés A, Gilabert J, Griffin JH. Immunoaf-finity purification of protein C with a calcium-dependent monoclonal antibody. Rev Iberoamer Tromb Haemost 1991; 4: 25-28
- 21 España F, Estellés A, Aznar J, Gilabert J. Assay of protein C in human plasma: Comparison of amidolytic, coagulation and immunochemical assays. Thromb Res 1986; 44: 771-782
- 22 Suzuki K, Nishioka J, Hashimoto S. Protein C inhibitor: Purification from human plasma and characterization. J Biol Chem 1983; 258: 163-168
- 23 Heeb MJ, Griffin JH. Physiologic inhibition of human activated protein C by alpha 1-antitrypsin. J Biol Chem 1988; 263: 11613-11616
- 24 España F. Complexes of activated protein C with its inhibitors, in. Aznar J, España F. (eds) Protein C pathway; Barcelona - Berlin, Springer-Verlag: 1991. pp 61-75
- 25 Tabernero D, España F, Vicente V, Estellés A, Gilabert J, Aznar J. Protein C inhibitor and other components of the protein C pathway in patients with acute deep vein thrombosis during heparin treatment. Thromb Haemost 1990; 63: 380-382
- 26 Vicente V, España F, Tabernero D, Aznar J, Estellés A, Griffin JH. Evidence of activation of the protein C pathway during acute vascular damage induced by Mediterranean spotted fever. Blood 1991; 78: 416-422
- 27 España F, Gruber A, Heeb MJ, Hanson SR, Harker LA, Griffin JH. In vivo and in vitro complexes of activated protein C with two inhibitors in baboon. Blood 1991; 77: 1754-1760
- 28 Sheth SB, Carvalho AC. Protein S and C alterations in acutely ill patients. Amer J Hematol 1991; 36: 14-19
- 29 Taylor Jr FB, Chang A, Esmon CT, D’Angelo A, Vigano-D’Angelo S, Blick KE. Protein C prevents the coagulopathic and lethal effects of E. coli infusion in the baboon. J Clin Invest 1987; 79: 918-925
- 30 Esmon CT. The protein C anticoagulant pathway. Arterioscler Thromb 1992; 12: 135-145
- 31 Snow TR, Deal MT, Dickey DT, Esmon CT. Protein C activation following coronary artery occlusion in the in situ porcine heart. Circulation 1991; 84: 293-299
- 32 España F, Vicente V, Vazquez L, Estellés A, Sánchez-Cuenca J, Aznar J. Activation of protein C and complex formation between protein C inhibitor and tissue plasminogen activator during thrombolytic therapy. Fibrinolysis 1993; 7: 308-315
- 33 Gruber A, Pal A, Kiss RG, Sas G, Griffin JH. Generation of activated protein C during thrombolysis. Lancet 1993; 342: 1275-1276
- 34 España F, Gilabert J, Vicente V, Estellés A, Vazquez L, Hendí S, Aznar J. Activated protein C:α1-antitrypsin (APC:α1AT) complex as a marker for in vitro diagnosis of prethrombotic states. Thromb Res 1992; 66: 499-508
- 35 Dahlbäck B, Carlsson M, Svensson PJ. Familial thrombophilia due to a previously unrecognized mechanism characterized by poor anticoagulant response to activated protein C: Prediction of a cofactor to activated protein C. Proc Natl Acad Sci USA 1993; 90: 1004-1008
- 36 Koster T, Roosendal FR, de Ronde H, Briet E, Vandenbroucke JP, Bertina R. Venous thrombosis due to poor anticoagulant response to activated protein C: Leiden thrombophilia study. Lancet 1993; 342: 1503-1506
- 37 Griffin JH, Evatt B, Wideman C, Fernandez JA. Anticoagulant protein C pathway defective in majority of thrombophilic patients. Blood 1993; 82: 1989-1993
- 38 Svensson PJ, Dahlback B. Resistance to activated protein C as a basis for venous thrombosis. N Engl J Med 1994; 330: 517-522
- 39 Bauer KA, Broekmans AW, Bertina RM, Conard J, Horellou M, Samama MM, Rosenberg RD. Hemostatic enzyme generation in the blood of patients with hereditary protein C deficiency. Blood 1988; 71: 1418-1426