Protein C Inhibitor Regulates the Thrombin-Thrombomodulin Complex in the Up- and Down Regulation of TAFI Activation

Summary

Thrombin Activatable Fibrinolysis Inhibitor (TAFI) is a carboxypeptidase B-like proenzyme that after activation by thrombin down regulates fibrinolysis. Thrombomodulin (TM) stimulates the activation of both TAFI and protein C whereas activated protein C (APC) inhibits the activation of TAFI by down regulating thrombin generation. Recently, protein C inhibitor (PCI) was identified as a potent inhibitor of thrombin bound to TM and it can thereby regulate the balance between TAFI activation, and inhibition of TAFI activation by APC. Both in a purified system and in plasma, activation of TAFI and protein C by IIa-TM could be inhibited by PCI. Previously we found in plasma that at low concentrations (~1 nM), TM predominantly stimulated the activation of TAFI whereas at higher concentrations of TM (~10 nM) the activation of protein C resulted in inhibition of the activation of TAFI. In agreement with this, PCI inhibited the activation of TAFI at 1 nM TM whereas at 10 nM TM PCI inhibited the activation of protein C resulting in an increase in the activation of TAFI. This suggests that PCI can up regulate TAFI activation by inhibiting the protein C activation. PCI may therefore be an important regulator in the balance between coagulation and fibrinolysis by differentially inhibiting the activation of TAFI and of protein C. The local TM concentration plays an important role in the outcome of this process.

Keywords

Fibrinolysis - TAFI - carboxypeptidase U - protein C - protein C inhibitor - thrombomodulin

• References

• 1 Huber R, Carell RW. Implications of the three dimensional structure of α₁-antitrypsin for the structure and function of serpins. Biochemistry 1989; 28: 8951-66.
• 2 Suzuki K, Deyashiki Y, Nishioka J, Kurachi K, Akira M, Yamamoto S, Hashimoto S. Characterization of a cDNA for human protein C inhibitor. A new member of the serine protease inhibitor superfamily. J Biol Chem 1987; 262: 611-6.
• 3 Marlar RA, Griffin JH. Deficiency of protein C inhibitor in combined factor V/VIII disease. J Clin Invest 1980; 66: 1186-9.
• 4 Suzuki K, Nishioka J, Hashimoto H. Protein C inhibitor: Purification from human plasma and characterization. J Biol Chem 1983; 258: 163-8.
• 5 Pratt CW, Church FC. General features of the heparin-binding serpins antithrombin, heparin cofactor II and protein C inhibitor. Blood Coagul Fibrinolysis 1993; 14: 479-90.
• 6 Pratt CW, Church FC. Heparin binding to protein C inhibitor. J Biol Chem 1992; 267: 8789-94.
• 7 Cooper ST, Church FC. Reactive site mutants of protein C inhibitor. Biochim Biophys Acta 1995; 1246: 29-33.
• 8 Meijers JCM, Kanters DHAJ, Vlooswijk RAA, van Erp HE, Hessing M, Bouma BN. Inactivation of human plasma kallikrein and factor XIa by protein C inhibitor. Biochemistry 1988; 27: 4231-7.
• 9 Stump DC, Thienpoint M, Collen D. Purification and characterization of a novel inhibitor of urokinase from human urine. J Biol Chem 1986; 261: 12759-66.
• 10 Heeb MJ, Espana F, Geiger M, Collen D, Stump DC, Griffin JH. Immuno-logical identity of heparin-dependent plasma and urinary protein C inhibitor and plasminogen activator inhibitor-3. J Biol Chem 1987; 262: 15813-6.
• 11 Rezaie AR, Cooper ST, Church FC, Esmon CT. Protein C inhibitor is a potent inhibitor of the thrombin-thrombomodulin complex. J Biol Chem 1995; 270: 25336-9.
• 12 Elisen MG, von dem Borne PAK, Bouma BN, Meijers JCM. Protein C inhibitor acts as a procoagulant by inhibiting the thrombomodulin-induced activation of protein C in human plasma. Blood 1998; 91: 1542-7.
• 13 Esmon CT. Thrombomodulin as a model of molecular mechanisms that modulate protease specificity and function at the vessel surface. FASEB J 1995; 9: 946-55.
• 14 Rosing J, Tans G. Coagulation factor V: an old star shines again. Thromb Haemost 1997; 78: 427-33.
• 15 Esmon CT. The regulation of natural anticoagulant pathways. Science 1987; 235: 1348-52.
• 16 Bick RL, Ancypa D. Blood protein defects associated with thrombosis. Laboratory assessment. Clin Lab Med 1995; 15: 125-63.
• 17 Griffin JH, Evatt B, Zimmerman TS, Kleiss AJ, Wideman C. Deficiency of protein C in congenital thrombotic disease. J Clin Invest 1981; 68: 1370-3.
• 18 Bertina RM. Hereditary protein S deficiency. Haemostasis 1985; 15: 241-6.
• 19 Bajzar L, Morser J, Nesheim M. TAFI, or plasma procarboxypeptidase B, couples the coagulation and fibrinolytic cascades through the thrombinthrombomodulin complex. J Biol Chem 1996; 271: 16603-8.
• 20 Bajzar L, Manuel R, Nesheim ME. Purification and characterization of TAFI, a thrombin-activable fibrinolysis inhibitor. J Biol Chem 1995; 270: 14477-84.
• 21 Eaton DL, Malloy BE, Tsai SP, Henzel W, Drayna D. Isolation, molecular cloning, and partial characterization of a novel carboxypeptidase B from human plasma. J Biol Chem 1991; 266: 21833-8.
• 22 Wang W, Hendriks DF, Scharpé SS. Carboxypeptidase U a plasma carboxypeptidase with high affinity for plasminogen. J Biol Chem 1994; 269: 15937-44.
• 23 Wang W, Boffa PB, Bajzar L, Walker JB, Nesheim ME. A study of the mechanism of inhibition of fibrinolysis by activated thrombin-activable fibrinolysis inhibitor. J Biol Chem 1998; 273: 27176-81.
• 24 Redlitz A, Tan AK, Eaton DL, Plow EF. Plasma carboxypeptidases as regulators of the plasminogen system. J Clin Invest 1995; 96: 2534-8.
• 25 Von dem Borne PAK, Meijers JCM, Bouma BN. Feedback activation of factor XI by thrombin in plasma results in additional formation of thrombin that protects fibrin clots from fibrinolysis. Blood 1995; 86: 3035-42.
• 26 Von dem Borne PAK, Bajzar L, Meijers JCM, Nesheim ME, Bouma BN. Thrombin- mediated activation of factor XI results in a thrombin-activatable fibrinolysis inhibitor- dependent inhibition of fibrinolysis. J Clin Invest 1997; 99: 2323-7.
• 27 Minnema MC, Friederich PW, Levi M, Von dem Borne PAK, Mosnier LO, Meijers JCM, Biemond BJ, Hack CE, Bouma BN, ten Cate H. Enhancement of rabbit jugular vein thrombolysis by neutralization of factor XI – In vivo evidence for a role of factor XI as an anti-fibrinolytic factor. J Clin Invest 1998; 101: 10-4.
• 28 Gresele P, Momi S, Berrettini M, Nenci GG, Schwarz HP, Semeraro N, Colucci M. Activated human protein C prevents thrombin-induced thromboembolism in mice – Evidence that activated protein C reduces intravascular fibrin accumulation through the inhibition of additional thrombin generation. J Clin Invest 1998; 101: 667-76.
• 29 de Fouw NJ, Haverkate F, Bertina RM. Protein C and fibrinolysis: a link between coagulation and fibrinolysis. Adv Exp Med Biol 1990; 281: 235-43.
• 30 Bajzar L, Fredenburgh JC, Nesheim ME. The activated protein C-mediated enhancement of tissue-type plasminogen activator induced fibrinolysis in a cell-free system. J Biol Chem 1990; 265: 16948-54.
• 31 Comp PC, Esmon CT. Generation of fibrinolytic activity by infusion of activated protein C into dogs. J Clin Invest 1981; 68: 1221-8.
• 32 Bajzar L, Nesheim ME, Tracy PB. The profibrinolytic effect of activated protein C in clots formed from plasma is TAFI-dependent. Blood 1996; 88: 2093-100.
• 33 Mosnier LO, Meijers JCM, Bouma BN. Regulation of fibrinolysis in plasma by TAFI and protein C is dependent on the concentration of thrombomodulin. Thromb Haemost 2001; 85: 5-11.
• 34 Hackeng TM, Hessing M, van ’t Veer C, Meijer-Huizinga F, Meijers JCM, de Groot PG, van Mourik JA, Bouma BN. Protein S binding to human endothelial cells is required for expression of cofactor activity for activated protein C. J Biol Chem 1993; 268: 3993-4000.
• 35 Elisen MG, Maseland MH, Church FC, Bouma BN, Meijers JCM. Role of the A+ helix in heparin binding to protein C inhibitor. Thromb Haemost 1996; 75: 760-6.
• 36 Meijers JCM. Regulation of the blood coagulation mechanism by plasma proteinase inhibitors. PhD Thesis, State University of Utrecht 1988: 93-108.
• 37 Mosnier LO, Von dem Borne PAK, Meijers JCM, Bouma BN. Plasma TAFI levels influence the clot lysis time in healthy individuals in the presence of an intact pathway of coagulation. Thromb Haemost 1998; 80: 829-35.
• 38 Brunner J, Skrabal P, Hauser H. Single bilayer vesicles prepared without sonication. Physico-chemical properties. Biochim Biophys Acta 1976; 455: 322-31.
• 39 Von dem Borne PAK, Mosnier LO, Tans G, Meijers JCM, Bouma BN. Factor XI activation by meizothrombin: stimulation by phospholipid vesicles containing both phosphatidylserine and phosphatidylethanolamine. Thromb Haemost 1997; 78: 834-9.
• 40 Rouser G, Fleisher S, Yamamoto A. Two dimensional thin layer chromatographic separation of polar lipids and determination of phospholipids by phosphorus analysis of spots. Lipids 1970; 5: 494-6.
• 41 Kokame K, Zheng XL, Sadler JE. Activation of thrombin-activable fibrinolysis inhibitor requires epidermal growth factor-like domain 3 of thrombomodulin and is inhibited competitively by protein C. J Biol Chem 1998; 273: 12135-9.
• 42 Wang W, Nagashima M, Schneider M, Morser J, Nesheim ME. Elements of the primary structure of thrombomodulin required for efficient TAFI activation. J Biol Chem 2000; 275: 22942-7.
• 43 Nesheim M, Wang W, Boffa MB, Nagashima M, Morser J, Bajzar L. Thrombin, thrombomodulin and TAFI in the molecular link between coagulation and fibrinolysis. Thromb Haemost 1997; 78: 386-91.
• 44 Hall SW, Nagashima M, Zhao L, Morser J, Leung LL. Thrombin interacts with thrombomodulin, protein C, and thrombin-activatable fibrinolysis inhibitor via specific and distinct domains. J Biol Chem 1999; 274: 25510-6.
• 45 Aird WC, Edelberg JM, Weiler-Guettler H, Simmons WW, Smith TW, Rosenberg RD. Vascular bed-specific expression of an endothelial cell gene is programmed by the tissue microenviroment. J Cell Biol 1997; 138: 1117-24.
• 46 Bajaj MS, Kuppuswamy MN, Manepalli AN, Bajaj SP. Transcriptional expression of tissue factor pathway inhibitor, thrombomodulin and von willebrand factor in normal human tissues. Thromb Haemost 1999; 82: 1047-52.
• 47 Ishii H, Salem HH, Bell CE, Laposata EA, Majerus PW. Thrombomodulin, an endothelial anticoagulant protein, is absent from the human brain. Blood 1986; 67: 362-5.
• 48 Rosenberg RD, Aird WC. Vascular-bed-specific-hemostasis and hypercoagulable states. N Engl J Med 1999; 340: 1555-64.
• 49 Drake TA, Morrissey JH, Edgington TS. Selective cellular expression of tissue factor in human tissues: implications for disorders of hemostasis and thrombosis. Am J Pathol 1989; 134: 1087-97.
• 50 Esmon CT. The roles of protein C and thrombomodulin in the regulation of blood coagulation. J Biol Chem 1989; 264: 4743-6.
• 51 Busch C, Cancilla PA, DeBault LE, Goldsmith JC, Owen WG. Use of endothelium cultured on microcarriers as a model for the microcirculation. Lab Invest 1982; 47: 498-504.
• 52 Hosaka Y, Takahashi Y, Ishii H. Thrombomodulin in human plasma contributes to inhibit fibrinolysis through acceleration of thrombin-dependent activation of plasma procarboxypeptidase B. Thromb Haemost 1998; 79: 371-7.
• 53 Marlar RA, Kressin DC, Madden RM. Contribution of plasma protease inhibitors to the regulation of activated protein C in plasma. Thromb Haemost 1993; 69: 16-20.
• 54 Espana 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 baboons. Blood 1991; 77: 1754-60.
• 55 Broze Jr GJ, Higuchi DA. Coagulation-dependent inhibition of fibrinolysis: role of carboxypeptidase-U and the premature lysis of clots from hemophilic plasma. Blood 1996; 88: 3815-23.
• 56 Redlitz A, Nicolini FA, Malycky JL, Topol EJ, Plow EF. Inducible carboxypeptidase activity. A role in clot lysis in vivo. Circulation 1996; 93: 1328-30.
• 57 Klement P, Liao P, Bajzar L. A novel approach to arterial thrombolysis. Blood 1999; 94: 2735-43.