Hemophilia B is an X chromosome-linked recessive bleeding disorder. To develop a somatic gene therapy for this disease, we have examined whether mouse skeletal myoblasts can serve as efficient vehicles for systemic delivery of recombinant factor IX. When mouse myoblasts (C2C12) transduced with a Moloney murine leukemia virus-based vector containing the bacterial beta-galactosidase gene were inj...

A radioimmunoassay for alloantibodies (inhibitors) and heteroantibodies to human factor IX has been developed using radioiodinated human factor IX and formalin-fixed, heat-killed Staphylococcus aureus cells (Staph A). Staph A was used as a solid-phase adsorbent for immune complexes. The assay is specific, shows excellent correlation with factor IX coagulant neutralization assays in detecting al...

Context:  The major motivation for the preparation of the plasma derived biological medicine was the treatment of casualties from the Second World War.  Due to the high expenses for preparation of plasma derived products, achievement of self-sufficiency in human plasma biotechnological industry is an important goal for developing countries.Evidence Acquisition:  The complexity of the bloo...

Elevated circulatory levels of many blood coagulation factors are known to be a risk factor for deep vein thrombosis in humans. Here we report the first direct demonstration of a close association between elevated circulatory factor IX levels in mice with thrombosis as well as myocardial fibrosis. Transgenic mice overexpressing human factor IX at persistently high levels died at much younger ag...

To study the interrelationships of the major human coagulation pathways, factor X activation in normal and various deficient human plasmas was evaluated when clotting was triggered by dilute rabbit or human thromboplastin. Various dilutions of thromboplastin were added to plasma samples containing 3H-labeled factor X, and the time course of factor X activation was determined. At a 1/250 dilutio...

Two structurally different forms of activated human Factor IX (Factor IXaa and IXa8) have been previously reported to have essentially identical clotting activity in vitro. Although it has been shown that activated Factor IXChapel Hills an abnormal Factor IX isolated from the plasma of a patient with mild hemophilia B, and normal Factor IXaa are structurally very similar, the clotting activity ...

Residue K5 in factor IX gamma-carboxyglutamic acid (Gla) domain participates in binding endothelial cells/collagen IV. We injected recombinant factor IX containing mutations at residue 5 (K5A, K5R) into factor IX-deficient mice and compared their behavior with that of wild-type factor IX. The plasma concentration of factor IX that binds to endothelial cells/collagen IV (recombinant wild type an...

A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable fr...

We used a first-generation adenovirus vector (AVC3FIX5) to assess whether human factor IX could be expressed and detected in the rhesus macaque, which we have shown does not make high-titer antibodies to human factor IX protein. Three animals received 1 x 10(10) to 1 x 10(11) plaque-forming units per kilogram by intravenous injection. Human factor IX was present within 24 hours of vector admini...