Effect of von Willebrand factor coexpression on the synthesis and secretion of factor VIII in Chinese hamster ovary cells.

摘要: In plasma, antihemophilic factor (factor VIII) exists as a 200-kilodalton heavy-chain polypeptide in metal ion association with an 80-kilodalton light-chain polypeptide. This complex is bound by hydrophobic and hydrophilic interactions to large multimeric glycoprotein, von Willebrand (vWF). Accumulation of secreted human VIII activity expressed Chinese hamster ovary cells requires the addition serum growth medium, which provides vWF. Here we report that coexpression vWF resulted increased stable accumulation absence medium. coexpressing cells, cDNA transcription unit was transcribed yield mRNA efficiently translated. properly processed disulfide-bonded high-molecular-weight multimers similar those observed from endothelial cells. Nuclear run-on assays showed gene at level gene, but did not accumulate high levels cytoplasm. addition, although translation efficiency vWF, processing secretion primary product dramatically reduced compared These results demonstrate both are inefficient processes.