title: Stable expression of recombinant factor VIII molecules using a bovine papillomavirus vector.
abstract: The bleeding disorder in hemophilia A results from a deficiency or abnormality of Factor VIII (FVIII), a member of the coagulation cascade. FVIII is a large glycoprotein (approximately 350,000 daltons) that is activated by a series of proteolytic cleavages. During activation, a large internal domain (B domain) is removed, resulting in an active complex comprised of the amino and carboxyl subunits of the parental molecule. Using a bovine papillomavirus expression vector system, we have established stable, genetically engineered cell lines harboring either full-length FVIII cDNA or variant FVIII cDNA (delta FVIII), the latter containing an extensive deletion in the region encoding the B domain. We demonstrate that the two recombinant FVIII molecules manifest the biological attributes of native FVIII. Relative to full-length FVIII transformants, cells harboring delta FVIII cDNA are five to eight times more efficient in expressing coagulant activity. This difference is due to a post-transcriptional event.
mesh_terms: D052688:Bovine papillomavirus 1 / Q000235:genetics*; D002478:Cells, Cultured; D004492:Edetic Acid; D005169:Factor VIII / Q000235:genetics*; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006801:Humans; D009500:Neutralization Tests; D009693:Nucleic Acid Hybridization; D027383:Papillomaviridae / Q000235:genetics*; D012313:RNA / Q000032:analysis; D011994:Recombinant Proteins / Q000235:genetics; D013917:Thrombin
chemical_list: D011994:Recombinant Proteins; D012313:RNA; D005169:Factor VIII; D004492:Edetic Acid; D013917:Thrombin