Expression and fast preparation of biologically active recombinant human coagulation factor VII in CHO-K1 cells

Human coagulation factor VII (FVII) plays an important role in the blood coagulation process and exists in micro amounts in human plasma; therefore, any attempt at the large-scale production of FVII in significant quantities is challenging.The purpose of this study was to express and obtain biologically active recombinant FVII (rFVII) from Chinese hamster ovary K1 (CHO-K1) cells.The full-length FVII cDNA was isolated from a HepG2 cell line and then subcloned in pcDNA3.1 to construct an expression vector, pcDNA-FVII.CHO-K1 cells were transfected with 1 μg pcDNA-FVII.The cell line that stably expressed secretory FVII was screened using 900 μg/ mL G418.The FVII copy number in CHO-K1 cells was detected by quantitative polymerase chain reaction (qPCR).The rFVII was purified in ligand affinity chromatography medium.The purified protein was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis.The biological activity of the purified FVII protein was determined by a prothrombin time assay.Three cell lines that permanently expressed rFVII were screened.The