Recombinant-derived human Factor VIII was labeled intrinsically with [35S]methionine, and its binding to washed human platelets was studied. Binding measurements were performed by incubating Factor VIII and platelets for 15 min at room temperature in Tyrode's solution supplemented with Ca2+ (5.0 mM), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (5.0 mM), 0.50% bovine serum albumin, and th...

von Willebrand factor (vWF) is a multimeric glycoprotein that promotes platelet aggregation and stabilizes coagulation factor VIII in the plasma. vWF is also required for the stable accumulation of recombinant factor VIII secreted from cells in a heterologous expression system. In this report, we show that vWF can promote the in vitro reconstitution of factor VIII activity from dissociated heav...

The production of factor VIII inhibitor antibodies remains the most costly and serious complication in replacement therapy of hemophilia A. We investigated the clinical significance of CD4(+)CD25(high) T regulatory (Treg) cells in hemophilia patients. Our trial included 6 severe hemophilia A patients with factor VIII inhibitors, 6 hemophilia patients without inhibition of factor VIII, and 6 hea...

BACKGROUND & AIMS Prophylactic injections of factor VIII reduce the incidence of bleeds and slow the development of joint damage in people with hemophilia. The aim of this study was to identify optimal person-specific prophylaxis regimens for children with hemophilia A. METHODS Analytic and numerical methods were used to identify prophylaxis regimens which maximize the time for which plasma f...

When plasma is separated or recovered from a blood donation or when plasma is collected by plasmapheresis the end result is not just a fluid which can be used in the treatment of many medical conditions but a raw material which can be used for the production of specific life saving or life enhancing medications for a variety of conditions. These conditions include Haemophilia A and Haemophilia ...

Hemophilia A (HA) is a common bleeding disorder caused by the deficiency of factor VIII (FVIII) with an incidence of ~1 in 5000 male births. Replacement of FVIII is necessary to prevent and treat bleeding episodes. However, with multiple new drugs in addition to old standards, choosing among the different FVIII treatment options is harder than ever. There are FVIII products that are plasma deri...

Clotting factor V has a dual function in coagulation: after activation, procoagulant factor V stimulates the formation of thrombin, whereas anticoagulant factor V acts as a cofactor for activated protein C (APC) in the degradation of factor VIII/VIIIa, thereby reducing thrombin formation. In the present study, we evaluated whether plasma factor V levels, either decreased or increased, are assoc...

The partial thromboplastin time test provides a convenient and sensitive screening procedure for deficiencies of thromboplastic factors, especially factors VIII and IX. The test is carried out after preincubating the plasma for 10 minutes with kaolin, and Inosithin is used as a platelet substitute. The ;normal range' of the test has been estimated in terms of the differences encountered between...