Metabolite profiling of CHO cells: Molecular reflections of bioprocessing effectiveness

• Published in: Biotechnology journal Vol. 10; no. 9; pp. 1434 - 1445
• Main Authors: Sellick, Christopher A., Croxford, Alexandra S., Maqsood, Arfa R., Stephens, Gill M., Westerhoff, Hans V., Goodacre, Royston, Dickson, Alan J.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01-09-2015; WILEY‐VCH Verlag
• Subjects: Animals; Bioprocessing; Biotechnology - methods; CHO Cells; Cricetinae; Cricetulus; Culture Media - metabolism; Gas Chromatography-Mass Spectrometry; Gas chromatography-mass spectrometry (GC-MS); Glutamine synthetase; Intracellular Space - metabolism; Metabolomics; Metabolomics - methods; Recombinant antibody; Recombinant Proteins - metabolism; Metabolomics; Glutamine synthetase; Bioprocessing; Recombinant antibody; Gas chromatography-mass spectrometry (GC-MS)
• ISSN: 1860-6768; 1860-7314
• DOI: 10.1002/biot.201400664

Whilst development of medium and feeds has provided major advances in recombinant protein production in CHO cells, the fundamental understanding is limited. We have applied metabolite profiling with established robust (GC‐MS) analytics to define the molecular loci by which two yield‐enhancing feeds improve recombinant antibody yields from a model GS‐CHO cell line. With data across core metabolic pathways, that report on metabolism within several cellular compartments, these data identify key metabolites and events associated with increased cell survival and specific productivity of cells. Of particular importance, increased process efficiency was linked to the functional activity of the mitochondria, with the amount and time course of use/production of intermediates of the citric acid cycle, for uses such as lipid biosynthesis, precursor generation and energy production, providing direct indicators of cellular status with respect to productivity. The data provide clear association between specific cellular metabolic indicators and cell process efficiency, extending from prior indications of the relevance of lactate metabolic balance to other redox sinks (glycerol, sorbitol and threitol). The information, and its interpretation, identifies targets for engineering cell culture efficiency, either from genetic or environmental perspectives, and greater understanding of the significance of specific medium components towards overall CHO cell bioprocessing.
Chinese hamster ovary cells in culture can use medium components and nutrients to support growth (biomass) and/or production of desirable recombinant proteins. Understanding the metabolic events within the cell will allow for the design of nutrient feeding strategies to provide selective enhancement of recombinant protein production. This paper describes the pattern of metabolic changes associated with enhanced growth and recombinant protein production and provides a metabolic visualisation of key regulatory events that may be modified or engineered to improve production.