Oxygen supply for CHO cells immobilized on a packed-bed of Fibra-Cel® disks

Abstract

Packed-bed bioreactors (PBR) have proven to be efficient systems to culture mammalian cells at very high cell density in perfusion mode, thus leading to very high volumetric productivity. However, the immobilized cells must be continuously supplied with all nutrients in sufficient quantities to remain viable and productive over the full duration of the perfusion culture. Among all nutrients, oxygen is the most critical since it is present at very low concentration due to its low solubility in cell culture medium. This work presents the development of a model for oxygenation in a packed-bed bioreactor system. The experimental system used to develop the model was a packed-bed of Fibra-Cel disk carriers used to cultivate Chinese Hamster Ovary cells at high density ( approximately 6.1 x 10(7) cell/mL) in perfusion mode. With the help of this model, it was possible to identify if a PBR system is operated in optimal or sub-optimal conditions. Using the model, two options were proposed, which could improve the performance of the basal system by about twofold, that is, by increasing the density of immobilized cells per carrier volume from 6.1 x 10(7) to 1.2 x 10(8) cell/mL, or by increasing the packed-bed height from 0.2 to 0.4 m. Both strategies would be rather simple to test and implement in the packed-bed bioreactor system used for this study. As a result, it would be possible to achieve a substantial improvement of about twofold higher productivity as compared with the basal conditions.

Application of a Cell-Once-Through Perfusion Strategy for Production of Recombinant Antibody from rCHO Cells in a Centritech Lab II Centrifuge System

“…All animal cell cultures are aerobic processes in which the oxygen requirement varies between cell lines. The effects of oxygen concentration on animal cell cultures have been studied by many authors (26)(27)(28)(29)(30). Link et al reported that a dissolved oxygen concentration of 5% resulted in the lowest viable cell density and product concentration, likely due to oxygen limitation in the batch culture of CHO-K1 cell line (31).…”

Fluid dynamics and oxygen transport in a micro-bioreactor with a tissue engineering scaffold

“…Thus, the micro-bioreactor should be operated at Re above 500. However, to have an optimal concentration around 50% of saturation [37], the Reynolds number should be around 1000. to bottom surfaces. At a Re from 1000 to 2000, the minimum location moves towards the left edge.…”

Mass Production of Mesenchymal Stem Cells — Impact of Bioreactor Design and Flow Conditions on Proliferation and Differentiation

“…In fixed bed bioreactors cells are immobilized on or encapsulated in a stationary matrix consisting of particles densely packed in a cylindrical vessel. Several types of particles have been used to date: Macro-porous microcarriers, porous ceramic beads, porous glass beads, glass fibers, polyester discs, alginate beads and hydrogels [62,[231][232][233][234][235][236]. The culture medium is perfused through the bed of the bioreactor and supplies cells with nutrients while removing undesired metabolites.…”