Monoclonal antibody expression in mammalian cells.

In the past two decades, the production levels for monoclonal antibodies in mammalian expression systems have improved dramatically. Single cell productivity for monoclonal antibodies has increased 20-50 fold due to the improvements in expression hosts, expression vectors, cell culture media, and production processes. However, most of these improvements are proprietary to large pharmaceutical/biotech companies and involve large steel-tank bioreactors. Therefore, these processes are difficult for small companies and academic labs to reproduce. Transient expression in mammalian cells has recently been used very widely for monoclonal antibody expression. Cell line and expression vector engineering increased expression levels to several hundred milligrams per liter. The availability of highly effective transfection reagents and disposable bioreactors make the transient expression process an efficient and cost-effective way to make recombinant antibodies in large quantity. Here, we describe the protocols for small- to mid-scale transient expression of monoclonal antibodies in shake-flasks and for large-scale production in WAVE bioreactors.