How reliable are Chinese Hamster Ovary (CHO) cell genome-scale metabolic models?

Genome-scale metabolic models (GEMs) possess the power to revolutionise bioprocess and cell line engineering workflows by their ability to predict and understand whole cell metabolism in silico. Despite this potential, it is unclear how accurately GEMs can capture both intracellular metabolic states and extracellular phenotypes. Here, we present an analysis investigating this knowledge gap to determine the reliability of current Chinese Hamster Ovary (CHO) cell metabolic models. We introduce a new GEM, iCHO2441, and create CHO-S and CHO-K1 specific GEMs. These are compared against iCHO1766, iCHO2048 and iCHO2291. Model predictions are assessed via comparison with experimentally measured growth rates, gene essentialities, amino acid auxotrophies, and 13 C intracellular reaction rates. Our results highlight all CHO cell models are able to capture extracellular phenotypes and intracellular fluxes, with the updated GEM outperforming the original CHO cell GEM. Cell line-specific models were able to better capture extracellular phenotypes but failed to improve intracellular reaction rate predictions in this case. Ultimately, this work package provides an updated CHO cell GEM to the community and lays a foundation for the development and assessment of next-generation flux analysis techniques, highlighting areas for model improvements. This article is protected by copyright. All rights reserved.