title: Combining mechanistic and data-driven approaches to gain process knowledge on the control of the metabolic shift to lactate uptake in a fed-batch CHO process.
abstract: A growing body of knowledge is available on the cellular regulation of overflow metabolism in mammalian hosts of recombinant protein production. However, to develop strategies to control the regulation of overflow metabolism in cell culture processes, the effect of process parameters on metabolism has to be well understood. In this study, we investigated the effect of pH and temperature shift timing on lactate metabolism in a fed-batch Chinese hamster ovary (CHO) process by using a Design of Experiments (DoE) approach. The metabolic switch to lactate consumption was controlled in a broad range by the proper timing of pH and temperature shifts. To extract process knowledge from the large experimental dataset, we proposed a novel methodological concept and demonstrated its usefulness with the analysis of lactate metabolism. Time-resolved metabolic flux analysis and PLS-R VIP were combined to assess the correlation of lactate metabolism and the activity of the major intracellular pathways. Whereas the switch to lactate uptake was mainly triggered by the decrease in the glycolytic flux, lactate uptake was correlated to TCA activity in the last days of the cultivation. These metabolic interactions were visualized on simple mechanistic plots to facilitate the interpretation of the results. Taken together, the combination of knowledge-based mechanistic modeling and data-driven multivariate analysis delivered valuable insights into the metabolic control of lactate production and has proven to be a powerful tool for the analysis of large metabolic datasets.
authors.affiliation: Dept. of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői Út, Budapest, H-1103, Hungary.|Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria.
authors.forename: Dénes
authors.initials: D
authors.lastname: Zalai
authors.affiliation: Dept. of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői Út, Budapest, H-1103, Hungary.
authors.forename: Krisztina
authors.initials: K
authors.lastname: Koczka
authors.affiliation: Dept. of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői Út, Budapest, H-1103, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Párta
authors.affiliation: Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria.|CD Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Vienna, Austria.
authors.forename: Patrick
authors.initials: P
authors.lastname: Wechselberger
authors.affiliation: Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria.|CD Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Vienna, Austria.
authors.forename: Tobias
authors.initials: T
authors.lastname: Klein
authors.affiliation: Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria.|CD Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Herwig
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D016466:CHO Cells; D018929:Cell Culture Techniques / Q000379:methods*; D016000:Cluster Analysis; D006224:Cricetinae; D003412:Cricetulus; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D016018:Least-Squares Analysis; D064688:Metabolic Flux Analysis / Q000379:methods*; D015999:Multivariate Analysis; D011994:Recombinant Proteins / Q000378:metabolism; D013696:Temperature
chemical_list: D000911:Antibodies, Monoclonal; D011994:Recombinant Proteins; D019344:Lactic Acid
keywords: PLS-R; lactate metabolism; mammalian cell culture; metabolic flux analysis; multivariate experimental design