Two novel inhibitory anti-human factor XI antibodies prevent cessation of blood flow in a murine venous thrombosis model

Summary

Coagulation factor XI (FXI) is a promising target for anticoagulation, because of its major role in thrombosis and relatively minor role in haemostasis. This implies that inhibition of FXI can prevent thrombosis without causing bleeding. It was our aim to investigate the antithrombotic properties of two novel inhibitory anti-human FXI antibodies (αFXI-175 and αFXI-203). The in vitro properties of both antibodies were analysed using standard clotting assays and calibrated automated thrombography. For the in vivo model we used FXI knockout mice, in which FXI plasma levels were restored with purified human FXI. Thrombosis was induced by applying ferric chloride to the vena cava inferior, after which time to occlusion was analysed. A tail bleeding assay was used to investigate the safety of both antibodies. Using calibrated automated thrombography, both antibodies inhibited thrombin generation initiated via the intrinsic pathway. In contrast, upon tissue factor (TF)-initiated thrombin generation, αFXI-203 did not inhibit thrombin generation, while αFXI-175 inhibited thrombin generation only at low concentrations of TF. In the murine thrombosis model, the vena cava inferior remained patent for 25 minutes (min) in mice treated with αFXI-175 and for 12.5 min in αFXI-203 treated animals, which was significantly longer than in placebo-treated animals (5 min, p<0.05). Neither antibody caused severe blood loss in a tail bleeding assay. In conclusion, the two inhibitory antibodies against FXI prevented cessation of blood flow in a murine thrombosis model without inducing a bleeding tendency.

Keywords

Coagulation - factor XI - thrombosis - murine models

• References

• 1 Davie EW, Fujikawa K, Kisiel W. The coagulation cascade: initiation, maintenance, and regulation. Biochemistry 1991; 30: 10363-10370.
• 2 Bauer KA. New anticoagulants. Curr Opin Hematol 2008; 15: 509-515.
• 3 Levine MN, Raskob G, Beyth RJ. et al. Hemorrhagic complications of anticoagulant treatment: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004; 126: 287S-310S.
• 4 Muller F, Gailani D, Renne T. FXI and XII as antithrombotic targets. Curr Opin Hematol 2011; 18: 349-355.
• 5 Bouma BN, Von dem Borne PA, Meijers JC. FXI and protection of the fibrin clot against lysis--a role for the intrinsic pathway of coagulation in fibrinolysis. Thromb Haemost 1998; 80: 24-27.
• 6 Salomon O, Steinberg DM, Koren-Morag N. et al. Reduced incidence of ischaemic stroke in patients with severe FXI deficiency. Blood 2008; 111: 4113-4117.
• 7 Salomon O, Steinberg DM, Zucker M. et al. Patients with severe FXI deficiency have a reduced incidence of deep-vein thrombosis. Thromb Haemost 2011; 105: 269-273.
• 8 Meijers JC, Tekelenburg WL, Bouma BN. et al. High levels of coagulation FXI as a risk factor for venous thrombosis. N Engl J Med 2000; 342: 696-701.
• 9 Yang DT, Flanders MM, Kim H. et al. Elevated FXI activity levels are associated with an increased odds ratio for cerebrovascular events. Am J Clin Pathol 2006; 126: 411-415.
• 10 Doggen CJ, Rosendaal FR, Meijers JC. Levels of intrinsic coagulation factors and the risk of myocardial infarction among men: Opposite and synergistic effects of factors XI and XII. Blood 2006; 108: 4045-4051.
• 11 Rosen ED, Gailani D, Castellino FJ. FXI is essential for thrombus formation following FeCl3-induced injury of the carotid artery in the mouse. Thromb Haemost 2002; 87: 774-776.
• 12 Wang X, Cheng Q, Xu L. et al. Effects of factor IX or FXI deficiency on ferric chloride-induced carotid artery occlusion in mice. J Thromb Haemost 2005; 3: 695-702.
• 13 Wang X, Smith PL, Hsu MY. et al. Effects of FXI deficiency on ferric chloride-induced vena cava thrombosis in mice. J Thromb Haemost 2006; 4: 1982-1988.
• 14 Zhang H, Lowenberg EC, Crosby JR. et al. Inhibition of the intrinsic coagulation pathway FXI by antisense oligonucleotides: a novel antithrombotic strategy with lowered bleeding risk. Blood 2010; 116: 4684-4692.
• 15 Seligsohn U. FXI deficiency in humans. J Thromb Haemost 2009; 7 (Suppl. 01) 84-87.
• 16 Colman RW, Scott CF. When and where is FXI activated by thrombin?. Blood 1996; 87: 2089
• 17 Von dem Borne PA, Bajzar L, Meijers JC. et al. Thrombin-mediated activation of FXI results in a thrombin-activatable fibrinolysis inhibitor-dependent inhibition of fibrinolysis. J Clin Invest 1997; 99: 2323-2327.
• 18 Gailani D, Renne T. The intrinsic pathway of coagulation: a target for treating thromboembolic disease?. J Thromb Haemost 2007; 5: 1106-1112.
• 19 Lip GY. Stroke in atrial fibrillation: epidemiology and thromboprophylaxis. J Thromb Haemost 2011; 9 (Suppl. 01) 344-351.
• 20 van Es J, Eerenberg ES, Kamphuisen PW. et al. How to prevent, treat, and overcome current clinical challenges of VTE. J Thromb Haemost 2011; 9 (Suppl. 01) 265-274.
• 21 Pendleton RC, Rodgers GM, Hull RD. Established venous thromboembolism therapies: heparin, low molecular weight heparins, and vitamin K antagonists, with a discussion of heparin-induced thrombocytopenia. Clin Chest Med 2010; 31: 691-706.
• 22 Diaz JA, Obi AT, Myers Jr. DD, Wrobleski SK, Henke PK, Mackman N. et al. Critical review of mouse models of venous thrombosis. Arterioscler Thromb Vasc Biol 2012; 32: 556-562.
• 23 Hemker HC, Giesen P, AlDieri R. et al. The calibrated automated thrombogram (CAT): a universal routine test for hyper- and hypocoagulability. Pathophysiol Haemost Thromb 2002; 32: 249-253.
• 24 Meijers JC, Mulvihill ER, Davie EW. et al. Apple four in human blood coagulation FXI mediates dimer formation. Biochemistry 1992; 31: 4680-4684.
• 25 Cho J, Furie BC, Coughlin SR. et al. A critical role for extracellular protein disulfide isomerase during thrombus formation in mice. J Clin Invest 2008; 118: 1123-1131.
• 26 Day SM, Reeve JL, Myers DD. et al. Murine thrombosis models. Thromb Haemost 2004; 92: 486-494.
• 27 Cheng Q, Tucker EI, Pine MS. et al. A role for FXIIa-mediated FXI activation in thrombus formation in vivo. Blood 2010; 116: 3981-3989.
• 28 Gailani D, Lasky NM, Broze Jr. GJ. A murine model of FXI deficiency. Blood Coagul Fibrinolysis 1997; 8: 134-144.
• 29 Renne T, Schmaier AH, Nickel KF. et al. In vivo roles of FXII. Blood 2012; 120: 4296-4303.
• 30 Puy C, Tucker EI, Wong ZC. et al. FXII promotes blood coagulation independent of FXI in the presence of long chain polyphosphate. J Thromb Haemost. 2013 Epub ahead of print.
• 31 Kravtsov DV, Matafonov A, Tucker EI. et al. FXI contributes to thrombin generation in the absence of FXII. Blood 2009; 114: 452-458.
• 32 Minnema MC, Friederich PW, Levi M. et al. Enhancement of rabbit jugular vein thrombolysis by neutralization of FXI. In vivo evidence for a role of FXI as an anti-fibrinolytic factor. J Clin Invest 1998; 101: 10-14.
• 33 Tucker EI, Marzec UM, White TC. et al. Prevention of vascular graft occlusion and thrombus-associated thrombin generation by inhibition of FXI. Blood 2009; 113: 936-944.