Bioprocess and Biosystems Engineering

, Volume 36, Issue 4, pp 469–487

A kinetic-metabolic model based on cell energetic state: study of CHO cell behavior under Na-butyrate stimulation

Authors

    • Canada Research Chair in Applied Metabolic Engineering, Department of Chemical EngineeringÉcole Polytechnique de Montréal
  • Olivier Henry
    • Canada Research Chair in Applied Metabolic Engineering, Department of Chemical EngineeringÉcole Polytechnique de Montréal
  • Mario Jolicoeur
    • Canada Research Chair in Applied Metabolic Engineering, Department of Chemical EngineeringÉcole Polytechnique de Montréal
Original Paper

DOI: 10.1007/s00449-012-0804-3

Cite this article as:
Ghorbaniaghdam, A., Henry, O. & Jolicoeur, M. Bioprocess Biosyst Eng (2013) 36: 469. doi:10.1007/s00449-012-0804-3

Abstract

A kinetic-metabolic model approach describing and simulating Chinese hamster ovary (CHO) cell behavior is presented. The model includes glycolysis, pentose phosphate pathway, TCA cycle, respiratory chain, redox state and energetic metabolism. Growth kinetic is defined as a function of the major precursors for the synthesis of cell building blocks. Michaelis–Menten type kinetic is used for metabolic intermediates as well as for regulatory functions from energy shuttles (ATP/ADP) and cofactors (NAD/H and NADP/H). Model structure and parameters were first calibrated using results from bioreactor cultures of CHO cells expressing recombinant t-PA. It is shown that the model can simulate experimental data for all available experimental data, such as extracellular glucose, glutamine, lactate and ammonium concentration time profiles, as well as cell energetic state. A sensitivity analysis allowed identifying the most sensitive parameters. The model was then shown to be readily adaptable for studying the effect of sodium butyrate on CHO cells metabolism, where it was applied to the cases with sodium butyrate addition either at mid-exponential growth phase (48 h) or at the early plateau phase (74 h). In both cases, a global optimization routine was used for the simultaneous estimation of the most sensitive parameters, while the insensitive parameters were considered as constants. Finally, confidence intervals for the estimated parameters were calculated. Results presented here further substantiate our previous findings that butyrate treatment at mid-exponential phase may cause a shift in cellular metabolism toward a sustained and increased efficiency of glucose utilization channeled through the TCA cycle.

Keywords

Metabolic modelingCHO cellsKinetic modelMetabolic regulationEnergy regulationSodium butyrate

Supplementary material

449_2012_804_MOESM1_ESM.docx (27 kb)
Supplementary material 1 (DOCX 27.3 kb)
449_2012_804_MOESM2_ESM.tif (560 kb)
Supplementary Fig. 1 Simulated data of intracellular metabolites for Control (solid line), and cultures with sodium butyrate addition at 48 h (NaBu-48h) (dashed line) and at 74 h (NaBu-74h) (dotted line). Axis units are mmol (106 cells)−1. Simulated values of intracellular concentrations showed to be within the range found in literature for TCA cycle intermediates (10−7–10−6 mmol (106 cells)−1) [39, 40], intracellular sugar phosphates (10−7–10−6 mmol (106 cells)−1) (CHO cells: [41]; Hepatic cells: [42]; MDCK cells: [43]), intracellular glutamine (10−7–10−6 mmol (106 cells)−1) and glutamate (10−6–10−5 mmol (106 cells)−1) (CHO cells: [44, 45]; HEK-293 cells: [45]). (TIFF 560 kb)

Copyright information

© Springer-Verlag 2012