Expression vector and cell line engineering is the basis for expression and industrial production of biopharmaceuticals. The ultimate goal is to obtain clonal cell lines that secrete the protein of interest with high cell-specific productivity, and at consistently high levels over an extended number of cell generations, allowing for scale-up and cost-efficient large-scale manufacturing. Productivity and stability of expression are thus the prerequisites for developing commercially viable processes…
Tag: <span>cell line development</span>
Organizations developing biopharmaceuticals are often faced with the challenge of developing, as rapidly as possible, a production system for a recombinant protein or antibody intended for use in clinical trials. For expression of antibodies and other proteins with complex post-translational modifications, Chinese hamster ovary (CHO) cells are often the host of choice. However, isolation of CHO cell lines producing even moderate levels of a protein of interest is usually a lengthy process due to the need for at least one and usually several gene amplification steps. Gene amplification, which is usually accomplished through the dihydrofolate reductase (dhfr)/methotrexate system, is a requirement for most CHO expression vectors because the absolute expression level from each copy of an integrated expression plasmid is generally very low…