Highly purified, fibrinogen-free human gel electrophoresis. The split products factor VIII was incubated with plasmin, were not anticoagulant in the factor and the liberated split products of the VIII activity assay. In fact, the breakfactor VIII were analyzed by gel filtradown products in the hydrolysate intion, acrylamide gel electrophoresis, creased the factor VIII activity of bioassay, and ...

Factor VIII activation by thrombin is the result of a proteolytic cleavage of the procoagulant component. These studies examine the effect of human antibody on this activation step in a solid phase immunoadsorbent assay system. Radiolabeled factor VIII antibody: factor VIII protein immune complexes were bound to agarose beads by mouse monoclonal antifactor VIII R:Ag antibody. The incubation of ...

Acquired factor VIII deficiency is very rare, often fatal. It is associated with pregnancy, autoimmune diseases, malignancy, and drugs, although no underlying cause is found in 50%. A 49-year-old male was referred with right shoulder bruising. The coagulation test showed a prolonged activated partial thromboplastin time. The factor VIII level was less than 1%, and the factor VIII inhibitor anti...

I NHIBITORS to factor VIII develop in approximately 1 5% of patients with hemophilia with an incidence of approximately 8 per 1,000 patient-years of observation.’ Clinically, these can be divided into high response inhibitors, which exhibit an anamnestic response after exposure to factor VIII, and low response inhibitors, which do not exhibit significant anamnesis.2 Because of their neutralizin...

Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIll-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical and immunologic properties, and have unique and essential T HE IMPORTANCE of factor VIII in hemostasis and bl...

Desmopressin increases endogenous factor VIII levels in hemophilia A. Large inter-individual variation in the response to desmopressin is observed. Patients with a lower baseline factor VIII activity tend to show a reduced response, therefore, desmopressin is less frequently used in moderate hemophilia A patients (baseline factor VIII activity 1-5 international units/deciliter), even though fac...

BACKGROUND: Elevated plasma levels of coagulation factor VIII are a strong risk factor for pulmonary emboli and deep venous thromboses. OBJECTIVES: To identify reversible biomarkers associated with high factor VIII, and assess potential significance in a specific at-risk population. PATIENTS/METHODS: 609 patients with hereditary haemorrhagic telangiectasia were recruited prospectively in two se...

Immune Tolerance Therapy for Haemophilia A Patients with Acquired Factor VIII Alloantibodies: Comprehensive Analysis of Experience at a Single Institution Eleven children with severe haemophilia A associated with the IVS 22 inversion and acquired high titre neutralising antibodies to factor VIII underwent immune tolerance induction. HLA class I and high resolution class II type is detailed for ...

One of the major binding sites for factor VIII inhibitors is located within the A2 domain. In this study, phage display technology was used to isolate 2 human monoclonal antibodies, termed VK34 and VK41, directed toward the heavy chain of factor VIII. The V(H) domain of a single-chain variable domain antibody fragment (scFv) VK34 is encoded by germline gene segment DP-10. Epitope-mapping studie...

Two forms of rabbit factor VIII procoagulant activity, distinguishable by size on gel filtration and ultracentrifugation, have been identified in normal rabbit plasma. These studies have been carried out with citrate-anticoagulated rabbit plasma obtained by cardiac puncture. Two peaks of factor VIII activity were obtained on agarose gel chromatography, using physiologic ionic strength buffers: ...