Oxidative stress‐alleviating strategies to improve recombinant protein production in CHO cells

Abstract

Large scale biopharmaceutical production of biologics relies on the overexpression of foreign proteins by cells cultivated in stirred tank bioreactors. It is well recognized and documented fact that protein overexpression may impact host cell metabolism and that factors associated with large scale culture, such as the hydrodynamic forces and inhomogeneities within the bioreactors, may promote cellular stress. The metabolic adaptations required to support the high‐level expression of recombinant proteins include increased energy production and improved secretory capacity, which, in turn, can lead to a rise of reactive oxygen species (ROS) generated through the respiration metabolism and the interaction with media components. Oxidative stress is defined as the imbalance between the production of free radicals and the antioxidant response within the cells. Accumulation of intracellular ROS can interfere with the cellular activities and exert cytotoxic effects via the alternation of cellular components. In this context, strategies aiming to alleviate oxidative stress generated during the culture have been developed to improve cell growth, productivity, and reduce product microheterogeneity. In this review, we present a summary of the different approaches used to decrease the oxidative stress in Chinese hamster ovary cells and highlight media development and cell engineering as the main pathways through which ROS levels may be kept under control.

Application of metabolic modeling for targeted optimization of high seeding density processes

“…The metabolite 2‐HB was strongly elevated in these cultures, indicating that it might be correlated to the improved productivity similar to its chemical analogons such as 3‐HB and NaB. Further reduction of ROS species via media optimization of antioxidant compounds such as vitamins, thiols, or α‐ketoacids as well as genetic engineering approaches could further improve culture longevity in HSD processes (Chevallier et al, 2020; Henry et al, 2020). At the same time strategies to induce cell cycle arrest and thereby increase specific productivities via temperature shifts or media components such as sodium butyrate, pentanoic acid, or resveratrol (Kumar et al, 2007; McHugh et al, 2020; Toronjo‐Urquiza et al, 2019) could enhance the productivity of HSD cultures.…”

Chlorella vulgaris Extract as a Serum Replacement That Enhances Mammalian Cell Growth and Protein Expression

“…C. vulgaris derived phenolic compounds possess potent antioxidative properties (Diaz-Vivancos et al, 2015), which may protect cells from serum deprivation-induced injury (Jung et al, 2017). Of interest, MAPK, PI3K/Akt and canonical Wnt are cross-species conserved signaling pathways that regulate protein expression (Proud, 2007), and manipulation thereof may potentially improve protein production yield (Chevallier et al, 2019). There is, however, to date no report that systematically evaluate the potential of C. vulgaris extract as a cell culture additive that could act as both a serum replacement and an inducer of protein expression.…”

Exploration the Mechanism of Doxorubicin-Induced Heart Failure in Rats by Integration of Proteomics and Metabolomics Data

“…PTP1B increases glutathione S-transferase (GSTs) protein levels by stimulating insulin receptor substrates, activating downstream PI3K, Akt/protein kinase B, ribosomal p70S6 kinase, and PKC ( Kim et al, 2006 ). Gamma 1-glutamyl-1-cysteine glycine (GSH), a tripeptide that can prevent oxidative stress and can be oxidized to form glutathione two sulfur (GSSG), when the ratio between oxidized and reduced GSH increases and glutathione is mixed with disulfide, will play a pathogenic factor in cardiovascular diseases ( Lu, 2013 ; Zima and Mazurek, 2016 ; Chevallier et al, 2020 ) The increased expression of glutathione S-transferase represents the imbalance of glutathione metabolism in cardiomyocytes, depletion of GSH increases and the ratio of GSH/GSSG decreases, which enhanced oxidative stress from ROS in cardiomyocytes ( Cramer et al, 2017 ; Ma et al, 2018 ). Among them, Gstp1 can sensitize cells to free radical-mediated damage by reducing the ability of reactive electrophiles to bind to glutathione, and its main active site is Val105, which is mainly associated with cardiovascular diseases ( Doney et al, 2005 ).…”