Generation and characterization of inhibitory nanobodies towards thrombin activatable fibrinolysis inhibitor.

TitleGeneration and characterization of inhibitory nanobodies towards thrombin activatable fibrinolysis inhibitor.
Publication TypeJournal Article
Year of Publication2010
AuthorsBuelens, K., G. Hassanzadeh-Ghassabeh, S. Muyldermans, A. Gils, and P. J. Declerck
JournalJ Thromb Haemost
Volume8
Issue6
Pagination1302-12
Date Published2010 Jun
ISSN1538-7836
KeywordsBiocatalysis, Carboxypeptidase U, Nanotechnology, Recombinant Proteins
Abstract

BACKGROUND AND OBJECTIVE: As activated thrombin-activatable fibrinolysis inhibitor (TAFIa) is a potent antifibrinolytic enzyme, the development of TAFI inhibitors is a new promising approach in the development of profibrinolytic drugs. We, therefore, aimed to generate nanobodies, camelid-derived single-domain antibodies towards TAFI.METHODS AND RESULTS: This study reports the generation and characterization of a panel of 22 inhibitory nanobodies. This panel represents a wide diversity in mechanisms for interference with the functional properties of TAFI as the nanobodies interfere with various modes of TAFI activation, TAFIa activity and/or TAFI zymogen activity. Nanobodies inhibiting TAFIa activity and thrombin/thrombomodulin-mediated TAFI activation revealed profibrinolytic properties in a clot lysis experiment with exogenously added thrombomodulin (TM), whereas nanobodies inhibiting plasmin-mediated TAFI activation only revealed profibrinolytic properties in a clot lysis experiment without TM. The results of in vitro clot lysis experiments provided evidence that inhibitory nanobodies penetrate the clot better compared with inhibitory monoclonal antibodies.CONCLUSIONS: These data suggest that the generated nanobodies are potent TAFI inhibitors and are a step forward in the development of a profibrinolytic drug. They might also be an excellent tool to unravel the role of the physiological activators of TAFI in various pathophysiological processes.

DOI10.1111/j.1538-7836.2010.03816.x
Alternate JournalJ. Thromb. Haemost.
PubMed ID20180900