Inhibitory antibody formation is a major complication of factor VIII replacement therapy in patients with hemophilia A. To better understand the pathogenesis of this immunologic reaction, we evaluated the role of T-cell costimulatory signals for antifactor VIII antibody formation in a murine model of hemophilia A. Repeated intravenous injections of factor VIII in these factor VIII–deficient mic...

Inhibitory antibody formation is a major complication of factor VIII replacement therapy in patients with hemophilia A. To better understand the pathogenesis of this immunologic reaction, we evaluated the role of T-cell costimulatory signals for antifactor VIII antibody formation in a murine model of hemophilia A. Repeated intravenous injections of factor VIII in these factor VIII-deficient mic...

Investigations were undertaken of the chemical nature and kinetics of interaction of three acquired inhibitors of Factor VIII. The inhibition was stoichiometric, one molecule of inhibitor (or one site on a molecule) being required to inactivate one molecule of Factor VIII. All three inhibitors were found to be monotypic antibodies of class IgG, Type K (gamma(2) kappa(2)). This appears to be the...

Immunologic methods were employed in an attempt to identify a potent procoagulant present in homogenates of human skin fibroblasts cultured in vitro. The activity of this procoagulant was restricted to the early stages of coagulation and was heretofore considered to be due to tissue factor (tissue thromboplastin, factor Ill) either alone or in combination with one or more of the first-stage coa...

A previously healthy elderly man with mucocutaneous bleeding was found to have a benign monoclonal lgG gammapathy associated with criteria for severe von Willebrand disease (Factor VIII procoagulant activity, Factor-VIII-related antigen, and ristocetin cofactor activity, <10% of normal). Associated qualitative abnormalities of factor VIII/von Willebrand factor were demonstrated by radiocrossed ...

we prepared a highly purified and relatively heat stable form of factor viii which contained 25 units per ml (u/ml) activity using peg-4000 and developed an effective and new manufacturing process. heat treatment was performed at 80°c for 72 hrs in the presence of different stabilizers. in our studies, we used different organic solvents as preservatives to maintain factor viii activity, since f...

INTRODUCTION Acquired factor VIII deficiency is a rare entity that can lead to severe and life-threatening bleeding. We describe a case of severe bleeding from the tongue secondary to acquired hemophilia and discuss treatment options, including aminocaproic acid and recombinant factor VIII, which have not been widely reported in the literature for the management of such patients. CASE PRESENT...

84 year old male with past medical history of myelodysplastic syndrome (MDS) presented with progressive subcutaneous and muscle bleed in the right forearm and arm. Workup revealed elevated activated partial thromboplastin time (aPTT) - 71.8 seconds (normal 23 - 32 seconds) which was persistently elevated after mixing study (37.1 seconds immediately and 51.1 seconds after 1 hour). Further labora...

Blood Transfus 2012; 10: 112-3 DOI 10.2450/2011.0064-11 © SIMTI Servizi Srl Dear Sir, In their timely letter on the current state of haemophilia therapy, Calizzani and Arcieri1 tackle two clinically important points: the effect of the source of factor VIII replacement therapy (plasmaderived or recombinant) on the cumulative incidence of factor VIII inhibitors in patients with haemophilia A; and...