High expression reduces an antibody response after neonatal gene therapy with B domain-deleted human factor VIII in mice.

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

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...

Reduction of the inhibitory antibody response to human factor VIII in hemophilia A mice by mutagenesis of the A2 domain B-cell epitope.

Approximately 25% of patients with hemophilia A develop inhibitory antibodies after treatment with factor VIII. Most of the inhibitory activity is directed against epitopes in the A2 and C2 domains. Anti-A2 inhibitory antibodies recognize a 25-residue segment bounded by R484-I508. Several antigenic residues in this segment have been identified, including R484, R489, and P492. The immunogenicity...

Phenotypic correction and long-term expression of factor VIII in hemophilic mice by immunotolerization and nonviral gene transfer using the Sleeping Beauty transposon system.

Hemophilia A is a lead candidate for treatment by gene therapy because small increments in the missing secreted protein product, coagulation factor VIII (FVIII), would result in substantial clinical amelioration. Clinically relevant therapy might be achieved by stably delivering a human FVIII cDNA to correct the bleeding disorder. We used the Sleeping Beauty (SB) transposon, delivered as naked ...

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 ...