Author Archives: Timothy Johnson

A Novel Seed-Train Process: Using High-Density Cell Banking, a Disposable Bioreactor, and Perfusion Technologies

A typical cell culture process begins with thawing of a cryopreserved cell-bank vial, followed by successive expansions into larger culture vessels such as shake flasks, spinners, Wave bags, and stirred bioreactors (1). When culture volume and cell density meet predetermined criteria, the culture is transferred to a production bioreactor in which cells continue to grow and express product. This approach presents several challenges. Shake flasks or spinners used in the initial stages require manual manipulations inside a laminar flow hood,…