LAUSR

Mammalian cell line development is critical to bioproduct manufacturing. Success requires selecting a line with desirable performance characteristics, including consistent expression throughout the proposed manufacturing window. Given the genetic and phenotypic flux inherent to immortalized lines such as Chinese hamster ovary cells, clonally‐derived cell line characterization is vital. We describe here the development and implementation of a novel addition to our characterization approach to ensure production cell line suitability: automated intracellular staining with statistical modeling. Case studies are presented which highlight this method's sensitivity to epigenetic expression effects, closing a gap left by our historically‐leveraged genetic suitability characterization. Additionally, we demonstrate how an orthogonal, complimentary assay can help identify opportunities for improvement in even a well‐established methodology such as our genetic suitability assessment. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:570–583, 2018