The procoagulant effects of factor V Leiden may be balanced against decreased levels of factor V and do not reflect in vivo thrombin formation in newborns

Summary

Thrombin regulation in newborns remains incompletely understood.We studied tissue factor-initiated thrombin formation in cord plasma in vitro, and the effects of Factor VLeiden (FVL) heterozygosity on thrombin regulation both in vitro and in vivo in newborns. Pregnant women with known thrombophilia (n=27) were enrolled in the study. Cord blood and venous blood at the age of 14 days were collected from 11 FVL heterozygous newborns (FVL-positive) and from 16 FVL-negative newborns. Prothrombin fragment F1+2 and coagulation factors were measured. Tissue factor-initiated thrombin formation was studied in cord platelet-poor plasma (PPP) of FVL-negative and -positive newborns, and in both PPP and platelet-rich plasma (PRP) of healthy controls. The endogenous thrombin potential (ETP) in cord PPP or PRP was ∼60% of that in adult plasma, while thrombin formation started ∼55% and ∼40% earlier in cord PPP and PRP, respectively. Further, in FVL-positive newborns thrombin formation started significantly earlier than in FVL-negative newborns. Exogenous activated protein C (APC) decreased ETP significantly more in cord than in adult PRP. In FVL-negative cord plasma 5nM APC decreased ETP by 17.4±3.5% (mean±SEM) compared with only 3.5±3.8% in FVL-positive cord plasma (p=0.01). FVL-positive newborns showed similar levels of F1+2 but significantly decreased levels of factor V compared with FVL negative newborns both in cord plasma (FV 0.82±0.07 U/ml vs. 0.98±0.05 U/ml, p=0.03) and at the age of two weeks (FV 1.15±0.04 U/ml vs. 1.32±0.05 U/ml, p=0.03). In conclusion, newborn plasma showed more rapid thrombin formation and enhanced sensitivity to APC compared with adult plasma. FVL conveyed APC resistance and a procoagulant effect in newborn plasma. Lack of elevated F1+2 levels in FVL-positive infants, however, suggested the existence of balancing mechanisms; one could be the observed lower level of factor V in FVL heterozygous newborns.

Keywords

Newborn - thrombin - activated protein C - factor V Leiden - platelet-rich plasma

• References

• 1 Andrew M, Paes B, Milner R. et al. Development of the human coagulation system in the full term infant. Blood 1987; 70: 165-72.
• 2 Andrew M, Paes B, Johnston M. Development of the human coagulation system in the neonate and young infant. Am J Pediatr Hematol Oncol 1990; 12: 95-104.
• 3 Yuen PMP, Yin JA, Lao TTH. FibrinopeptideA levels in maternal and newborn plasma. Eur J Obstet Gynecol Reprod Biol 1989; 30: 239-44.
• 4 Schneider DM, von Tempelhoff GF, Herrle B. et al. Maternal and cord blood hemostasis at delivery. J Perinat Med 1997; 25: 55-61.
• 5 Suarez CR, Walenga J, Mangogna LC. et al. Neonatal and maternal fibrinolysis: activation at time of birth. AmJ Hematol 1985; 19: 365-72.
• 6 Lao TTH, Yin JA, Yuen PMP. Coagulation and anticoagulation systems in newborns - correlation with their mothers at delivery. Gynecol Obstet Invest 1990; 29: 181-4.
• 7 Bertina RM, Koeleman BP, Koster T. et al. Mutation in blood coagulation factor V associated with resistance to activated protein C. Nature 1994; 343: 64-7.
• 8 Koster T, Rosendaal FR, de Ronde H. et al. Venous thromboembolism due to poor anticoagulant response to activated protein C: Leiden Thrombophilia Study. Lancet 1993; 342: 1503-6.
• 9 Svensson PJ, Dahlbäck B. Resistance to activated protein C as a basis for venous thrombosis. N Engl J Med 1994; 330: 517-22.
• 10 Dahlbäck B. The discovery of activated protein C resistance. J Thromb Haemost 2003; 01: 3-9.
• 11 Nicolaes GAF, Dahlbäck B. Factor V and thrombotic disease. Description of a janus-faced protein. Arterioscler Thromb Vasc Biol 2002; 22: 530-8.
• 12 Castoldi E, Rosing J. Factor V Leiden: a disorder of factor V anticoagulant function. Curr Opin Hematol 2004; 11: 176-81.
• 13 Andrew M, David M, Adams M. et al. Venous thromboembolic complications (VTE) in children: First analysis of the Canadian registry of VTE. Blood 1994; 83: 1251-7.
• 14 Hagstrom JN, Walter J, Bluebond-Langner R. et al. Prevalence of the factor V Leiden mutation in children and neonates with thromboembolic disease. J Pediatr 1998; 133: 777-81.
• 15 Petäjä J, Hiltunen L, Fellman V. Increased risk of intraventricular hemorrhage in newborn infants with thrombophilia. Pediatr Res 2001; 49: 643-6.
• 16 Schmidt B, Ofusu FA, Mitchell L. et al. Anticoagulant effects of heparin in neonatal plasma. Pediatr Res 1989; 25: 405-8.
• 17 Andrew M, Schmidt B, Mitchell L. et al. Thrombin generation in newborn plasma is critically dependent of the concentration of prothrombin. Thromb Haemost 1990; 63: 27-30.
• 18 Cvirn G, Gallistl S, Leschnik B. et al. Low tissue factor pathway inhibitor (TFPI) together with low antithrombin allows sufficient thrombin generation in neonates. J Thromb Haemost 2003; 01: 263-8.
• 19 Petäjä J, Fernandéz JA, Fellman V. et al. Upregulation of the antithrombotic proteinC pathway at birth. Pediatr Hematol Oncol 1998; 15: 489-99.
• 20 Schwartz HP, Muntean W, Wazke H. et al. Low total proteinS antigen but high proteinS activity due to decreased C4b-binding protein in neonates. Blood 1988; 71: 562-5.
• 21 Menashi S, Aurosseau MH, Gozin D. et al. High levels of circulating thrombomodulin in human foetuses and children. Thromb Haemost 1999; 81: 906-9.
• 22 Cvirn G, Gallistl S, Rehak G. et al. Elevated thrombin-forming capacity of tissue factor-activated cord compared with adult plasma. J Thromb Haemost 2003; 01: 1785-90.
• 23 Cvirn G, Gallistl S, Koestenberger M. et al. The anticoagulant action of recombinant human activated proteinC (rhAPC, Drotrecogin α activated): comparison between cord and adult plasma. Thromb Haemost 2004; 91: 912-8.
• 24 Hemker HC, Giesen P, Dieri RA. et al. Calibrated automated thrombin generation measurement in clotting plasma. Pathophysiol Haemost Thromb 2003; 33: 4-15.
• 25 Hemker HC, Giesen PLA, Ramjee M. et al. The Thrombogram: Monitoring thrombin generation in platelet rich plasma. Thromb Haemost 2000; 83: 389-91.
• 26 Vanschoonbeek K, Feijge MAH, van Kampen JW. et al. Initiating and potentiating role of platelets in tissue factor-induced thrombin generation in the presence of plasma: subject-dependent variation in thrombogram characteristics. J Thromb Haemost 2004; 02: 476-84.
• 27 Fernandez JA, Hackeng TM, Kojima K. et al. The carbohydrate moiety of factor V modulates inactivation by activated protein C. Blood 1997; 89: 4348-54.
• 28 Gould WR, Silveira JR, Tracy PB. Unique in vivo modifications of coagulation factor V produce a physically and functionally distinct platelet-derived cofactor. J Biol Chem 2004; 279: 2383-93.
• 29 Smirnov MD, Esmon CT. Phoshpatidylethanolamine incorporation into vesicles selectively enhances factor Va inactivation by activated protein C. J Biol Chem 1994; 269: 816-9.
• 30 Nicolaes GAF, Thomassen MCLGD, Tans G. et al. Effect of activated protein C on thrombin generation and on the thrombin potential in plasma of normal and APC-resistant individuals. Blood Coagul Fibrinol 1997; 08: 28-38.
• 31 Castoldi E, Brugge JM, Nicolaes GAF. et al. Impaired APC cofactor activity of factor V plays a major role in the APC resistance associated with the factor V Leiden (R506Q) and R2 (H1299R) mutations. Blood 2004; 103: 4173-9.
• 32 Zöller B, Holm J, Svensson P. et al. Elevated levels of prothrombin activation fragment 1+2 in plasma from patients with heterozygous Arg506 to Gln mutation in the factor V gene (APC-resistance) and/or inherited protein S deficiency. Thromb Haemost 1996; 75: 270-4.
• 33 Simioni P, Scarano L, Gavasso S. et al. Prothrombin fragment 1+2 and thrombin-antithrombin complex levels in patients with inherited APC resistance due to factor V Leiden mutation. Br J Haematol 1996; 92: 435-41.
• 34 Nowak-Göttl U, Vielhaber H. Elevated levels of soluble thrombomodulin in plasma from children with Arg 506 to Gln mutation in the factor V gene. Eur J Haematol 1997; 58: 51-5.
• 35 Rosendaal FR. Venous thrombosis: a multicausal disease. Lancet 1999; 353: 1167-73.
• 36 Petäjä J, Manco-Johnson MJ. ProteinC pathway in infants and children. Semin Thromb Hemost 2003; 29: 349-61.