Role of human factor VIII in factor X activation.

Expression of Biologically Active Recombinant B-Domain-Deleted Human Factor VIII in Mammalian Cells

THE ROLE OF VARIOUS STABILIZERS IN THE ACQUISITION OF THERMO-TOLER ANCE IN FACTOR VIII ACTIVITY

We prepared a highly purified and relatively heat stable form of factor VIII which contained 25 units per mL (u/mL) activity using PEG-4000 and developed an effective and new manufacturing process. Heat treatment was performed at 80°C for 72 hrs in the presence of different stabilizers. In our studies, we used different organic solvents as preservatives to maintain factor VIII activity, sin...

Bacterial Expression and Purification of C1C2 Domain of Human Factor VIII

With the aim of the production of human factor VIII antigen and its corresponding antibody an epitope coding fragment of the light-chain of hFVIII, fused to a His6-tag, was isolated and over-expressed in Escherichia coli. The over-expressed hFVIII-epitope containing peptide was confirmed by its reaction with a rabbit serum directed against native hFVIII as well as antiHis6-tag antibody. An expr...

Activation of factor X by factors IXa and VIII; a specific assay for factor IXa in the presence of thrombin-activated factor VIII.

We studied the activation of factor X by the intrinsic pathway of blood coagulation using a new assay of factor X activation. When factor X tritiated in its sialic acid residues is activated, activation can be measured by the release of tritiated activation peptide, and the initial rate of activation can be determined under varying conditions. In the presence of phospholipid and calcium ions, f...

The Effects of Novel Mutations in A1 Domain of Human Coagulation Factor VIII on Its Secretion Level in Cultured Mammalian Cells

Inefficient secretion of the human coagulation factor (hFVIII) in mammalian expression systems is one ofthe main causes of the hFVIII low expression level, attributed to its interaction with a chaperone known asBiP/GRP78. In order to improve secretion efficiency of the hFVIII, based on the higher secretion level of theporcine FVIII and analysis of the hFVIII A110 region, that ...