One pathway of blood coagulation, the extrinsic system, is initiated by a specific interaction between tissue factor, which is a membrane lipoprotein, and factor VII, one of the plasma coagulation factors. Factor VII was prepared from bovine plasma by adsorption onto and elution from BaSO(4). The eluate was chromatographed on DEAE-Sephadex and purified by preparative disc-gel electrophoresis. F...

By S00NA S. SETNA .-5’NI) S. J. ALTMAN I T IS \VELL KNO\VX that deficiencies of prothrombimi and proconvertin can I)e the cause of serious bleedimig.’’ In addition to recognized causes of these deficiencies, su(’h as inadequate imitake, aI)sorption or utilization of vitamin K, cases of unrecognized cause may be emicountered.6 To date, an acquired idiopathic deficiency of these two sul)stamices ...

Background: Factor VII concentrates are used in patients with congenital or acquired factor VII deficiency or treatment of hemophilia patients with inhibitors. In this research, immunoaffinity chromatography was used to purify factor VII from prothrombin complex (ProthrombinProconvertin-Stuart Factor-Antihemophilic Factor B or PPSB) which contains coagulation factors II, VII, IX and X. The aim ...

A family with a peculiar defect of factor VII is described. The propositi, a brother and sister, were born of a nonconsanguineous marriage and presented a mild to moderate bleeding tendency since childhood (epistaxis, excessive bleeding after tooth extraction). The coagulation pattern was characterized by a mildly prolonged prothrombin time, normal partial thromboplastin time, and normal Stypve...

Single chain factor VII is converted by limited proteolysis to its activated form, factor VIIa, by a number of blood coagulation proteases including factor IXa and factor Xa. We have determined the relative rate of human factor VII activation by human factors IXa and Xa in two different systems: one containing Ca++ and human bladder carcinoma (J82) cells, and the other containing Ca++ and mixed...

Factor VII activating protease (FSAP) is a circulating serine protease with high homology to fibrinolytic enzymes. A role in the regulation of coagulation and fibrinolysis is suspected based on in vitro studies demonstrating activation of FVII or pro-urokinase plasminogen activator (uPA). However, considering the paucity of any studies in animal models or any correlative studies in humans the r...

Recent studies suggested that modification of the membrane contact site of vitamin K-dependent proteins may enhance the membrane affinity and function of members of this protein family. The properties of a factor VII mutant, factor VII-Q10E32, relative to wild-type factor VII (VII, containing P10K32), have been compared. Membrane affinity of VII-Q10E32 was about 20-fold higher than that of wild...

Factor VII circulates as a single chain inactive zymogen (10 nmol/L) and a trace ( approximately 10-100 pmol/L) circulates as the 2-chain form, factor VIIa. Factor VII and factor VIIa were studied in a coagulation model using plasma concentrations of purified coagulation factors with reactions initiated with relipidated tissue factor (TF). Factor VII (10 nmol/L) extended the lag phase of thromb...