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bioRxiv · 10.1101/2023.03.09.531884

Debottlenecking and reformulating feed media for improved CHO cell growth and titer by data-driven and model-guided analyses

Abstract

Designing and selecting cell culture media and feed are a key strategy to maximize culture performance in industrial biopharmaceutical processes. However, this is a major challenge for therapeutic proteins production since mammalian cells are very sensitive to their culture environment and require specific nutritional needs to grow and produce high-quality proteins such as antibodies. In this regard, in our previous study, we developed data-driven and in-silico model-guided systematic framework to investigate the effect of growth media on Chinese hamster ovary (CHO) cell culture performance, allowing us to design a new media formulation. To expand our exploration to feed, in this study, we evaluated two chemically defined feed media, A and B, in Ambr15 bioreactor runs using a monoclonal antibody-producing CHO K1 cell line. The feeds had a significant impact on cell growth, longevity, viability, and productivity and toxic metabolites production. Specifically, concentrated feed A was not sufficient to support prolonged cell culture and high titer compared to feed B. The framework systematically characterized the major metabolic bottlenecks in the TCA cycle and its related amino acid transferase reactions, and identified key design components, such as asparagine, aspartate, and glutamate, needed for highly productive cell cultures. From our results, we designed three new feeds by adjusting the levels of those amino acids and successfully validated their effectiveness in promoting cell growth and/or titer.

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Park, S.-Y., Lee, D.-Y., Choi, D.-H., Song, J., Park, U., Cho, H., Hong, B. H., Silberberg, Y. R.. 2023-03-10. Debottlenecking and reformulating feed media for improved CHO cell growth and titer by data-driven and model-guided analyses. https://doi.org/10.1101/2023.03.09.531884

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