N. Mishra (1), E. Vercauteren (1), J. Develter (1), R. Bammens (1), P. J. Declerck (1), A. Gils (1)
(1) Laboratory for Pharmaceutical Biology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Leuven, Belgium
Thrombin activatable fibrinolysis inhibitor (TAFI) forms a molecular link between coagulation and fibrinolysis and is a putative target to develop profibrinolytic drugs. Out of a panel of monoclonal antibodies (MA) raised against TAFI-ACIIYQ, we selected MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4, which revealed high affinity towards human TAFI-TI-wt. MA-TCK11A9 was able to inhibit mainly plasmin-mediated TAFI activation, MA-TCK22G2 inhibited plasmin- and thrombin-mediated TAFI activation and MA-TCK27A4 inhibited TAFI activation by plasmin, thrombin and thrombin/thrombomodulin (T/TM) in a dose-dependent manner. These MA did not interfere with TAFIa activity. Using an eight-fold molar excess of MA over TAFI, all three MA were able to reduce clot lysis time significantly, i.e. in the presence of exogenous TM, MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4 reduced clot lysis time by 47 ± 9.1%, 80 ± 8.6% and 92 ± 14%, respectively, compared to PTCI. This effect was even more pronounced in the absence of TM i.e. MA-TCK11A9, MA-TCK22G2 and MA-TCK27A4 reduced clot lysis time by 90 ± 14%, 140 ± 12% and 147 ± 29%, respectively, compared to PTCI. Mutagenesis analysis revealed that residues at position 268, 272 and 276 are involved in the binding of MA-TCK11A9, residues 147 and 148 in the binding of MA-TCK22G2 and residue 113 in the binding of MA-TCK27A4. The present study identified three MA, with distinct epitopes, that impair the activation of human TAFI and demonstrated that MA-TCK11A9 which mainly impairs plasmin-mediated TAFI activation can also reduce significantly clot lysis time in vitro.
fibrinolysis, epitope mapping, monoclonal antibody, human TAFI, TAFI-inhibitors
Marie-Christine Alessi, Irène Juhan-Vague
Thromb Haemost 2008 99 6: 995-1000
Géraldine Lavigne-Lissalde1–3,*, Catherine Tarrade1,*, Priscilla Lapalud1, Sami Chtourou4, Jean-François Schved3, Claude Granier1, Sylvie Villard-Saussine1
Thromb Haemost 2008 99 6: 1090-1096
Sandip M. Kanse1, Mariana Parahuleva2, Lars Muhl1, Bettina Kemkes-Matthes3, Daniel Sedding2, Klaus T. Preissner1
Thromb Haemost 2008 99 2: 286-289
Atherosclerosis is an inflammatory and thrombotic disease, in which both CD4+ T cells and...
The May 2013 issue of Thrombosis and Haemostasis 109.5 is a clinically relevant 'state of the art'...
Starting with the April 2013 issue of "Thrombosis and Haemostasis" TH109.4, the ESC...