Previous studies have shown that factor IX and its activated form, factor IXa, bind to cultured vascular endothelial cells and that cell-bound factor IXa retains its procoagulant activity. The present studies provide evidence that factor IX bound to cultured bovine aortic endothelial cells can be activated. Factor IX activation was assessed by finding cleavage of the factor IX molecule on NaDod...

abstract  introduction: during extrinsic coagulation pathway, a complex is developed between factor vii, calcium and tissue factor (a cell membrane lipoprotein that is exposed after cell injury). factor vii needs calcium and vitamin k for its biologic activation. coronary artery disease (cad) can be induced by increased level and activity of the coagulation factors vii, viii and ix. in postmeno...

A persistent low-titer factor IX Inhibitor was discovered in a patIent with severe hemophllia B. The Inhibitor was very likely an immunoglobulin, since it was present in serum, was not dialyzable, retained its potency after heating to 56#{176}C, and was bound by staphylococcal protein A (SPA). When the hemophilia B patient with the inhibItor was given therapeutic infusions of factor Ix concentr...

DNA from nine hemophilia B patients who produce anti-factor IX inhibitors (antibodies), including two brothers, was analyzed by the Southern blotting method and hybridization with factor IX cDNA, intragenomic, and 3'-flanking probes. Two inhibitor patients were shown to have total deletions of the factor IX gene. Two other inhibitor patients, the brothers, were shown to have a presumably identi...

A genomic DNA library and the enzymatic DNA amplification technique were used to isolate human factor IX coding sequences of a hemophilia Bm variant, factor IXHilo. A point mutation that resulted in the substitution of a glutamine (CAG) for an arginine (CGG) at amino acid 180 was found in exon VI of the factor IX gene (G----A at nucleotide 20519). This mutation alters the carboxy terminal cleav...