RÉSUMÉ
Venous thromboembolic disease is a major cause of morbidity and mortality, necessitating antithrombotic therapy. A human monoclonal anti-factor (F)VIII antibody, LCL-mAb-LE2E9, produced by a lymphoblastoid cell line derived from a hemophilia A patient with inhibitor to wild-type but not mutant self FVIII, was previously reported to achieve efficient inhibition of thrombosis in an experimental vena cava thrombosis model in mice. Here, the antithrombotic efficacy of a recombinant DNA-derived version of this anti-FVIII antibody (rec-mAb-LE2E9) was tested in mice which carry a type II heparin binding site antithrombin deficiency mutation and display spontaneous chronic thrombosis in several sites including the penile vein of sexually active males. The recombinant anti-FVIII antibody (100 microg, repeated after 3 days) prevented thrombotic priapism in all treated males, whereas all control animals treated with saline (group of four animals) developed priapism within 6 days after mating (P < 0.05 for treated vs. saline). The rec-mAb-LE2E9 and the original LCL-mAb-LE2E9 were equally effective (five and seven males/group, respectively). These results confirm that FVIII inhibition represents a potent antithrombotic strategy, and show that both LCL-mAb-LE2E9 and rec-mAb-LE2E9 efficiently prevent thrombosis in a physiological model representative of thrombosis in patients with a severe prothrombotic risk.
Sujet(s)
Anticorps monoclonaux/pharmacologie , Déficit en antithrombine III/traitement médicamenteux , Facteur VIII/antagonistes et inhibiteurs , Fibrinolytiques/pharmacologie , Thrombose/prévention et contrôle , Animaux , Anticorps monoclonaux/pharmacocinétique , Antithrombine-III/génétique , Déficit en antithrombine III/sang , Déficit en antithrombine III/génétique , Sites de fixation/génétique , Facteur VIII/immunologie , Femelle , Fibrinolytiques/pharmacocinétique , Humains , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Priapisme/étiologie , Priapisme/anatomopathologie , Priapisme/prévention et contrôle , Protéines recombinantes/pharmacocinétique , Protéines recombinantes/pharmacologie , Thrombose/étiologie , Thrombose/anatomopathologieRÉSUMÉ
Soluble beta-amyloid protein precursors (beta-APPs) were studied in human brain and cerebrospinal fluid (CSF) after partial purification by ion exchange chromatography. Proteins were analysed in immunoblotting experiments using a monoclonal antibody directed against the N-terminal segment of the beta-APP 770, and by reverse enzymography. In the human brain and CSF, a protein which comigrates with the beta-APP 770 expressed by transfected CHO cells was able to inhibit trypsin.