Using Metabolomics to Identify Cell Line-Independent Indicators of Growth Inhibition for Chinese Hamster Ovary Cell-Based Bioprocesses

Abstract

Chinese hamster ovary (CHO) cells are widely used for the production of biopharmaceuticals. Efforts to improve productivity through medium design and feeding strategy optimization have focused on preventing the depletion of essential nutrients and managing the accumulation of lactate and ammonia. In addition to ammonia and lactate, many other metabolites accumulate in CHO cell cultures, although their effects remain largely unknown. Elucidating these effects has the potential to further improve the productivity of CHO cell-based bioprocesses. This study used untargeted metabolomics to identify metabolites that accumulate in fed-batch cultures of monoclonal antibody (mAb) producing CHO cells. The metabolomics experiments profiled six cell lines that are derived from two different hosts, produce different mAbs, and exhibit different growth profiles. Comparing the cell lines’ metabolite profiles at different growth stages, we found a strong negative correlation between peak viable cell density (VCD) and a tryptophan metabolite, putatively identified as 5-hydroxyindoleacetaldehyde (5-HIAAld). Amino acid supplementation experiments showed strong growth inhibition of all cell lines by excess tryptophan, which correlated with the accumulation of 5-HIAAld in the culture medium. Prospectively, the approach presented in this study could be used to identify cell line- and host-independent metabolite markers for clone selection and bioprocess development.

Secretion of a low‐molecular‐weight species of endogenous GRP94 devoid of the KDEL motif during endoplasmic reticulum stress in Chinese hamster ovary cells

“…engineering, [17][18][19][20] transcriptomics, 21 metabolomics, [22][23][24] and genomics. 25 Despite extensive research having been conducted on CHO cells, more research is required to further understand the biology of these cells in order to open new gateways for cell engineering.…”

Applications and analysis of hydrolysates in animal cell culture

“…Apart from contaminants, by-products from hydrolysates could also affect cell growth. A recent study has shown significant growth inhibition of the mAb-producing CHO-K1 GS-knockout and CHO-DG44 cells due to the accumulation of tryptophan in the culture (Alden et al 2020 ). In the same study, the tryptophan-derived metabolite, 5-HIAAId (5-hydroxyindolacetaldehyde), has been shown to have a detrimental effect on cell growth (Alden et al 2020 ).…”

“…A recent study has shown significant growth inhibition of the mAb-producing CHO-K1 GS-knockout and CHO-DG44 cells due to the accumulation of tryptophan in the culture (Alden et al 2020 ). In the same study, the tryptophan-derived metabolite, 5-HIAAId (5-hydroxyindolacetaldehyde), has been shown to have a detrimental effect on cell growth (Alden et al 2020 ). This observation is further supported by a separate study investigating the effects of increased levels of tryptophan by-products and riboflavin degradant (lumichrome), both of which are detrimental to cell growth (Zang et al 2011 ).…”

Using MVDA with Stoichiometric Balances to Optimize Amino Acid Concentrations in Chemically Defined CHO Cell Culture Medium for Improved Culture Performance

“…A challenge with such an approach is that over supplementation and consumption of certain amino acids can lead to the production of harmful byproducts. For instance, varying the amount of essential amino acid concentrations can lead to the differential regulation of amino acid metabolic pathways that could ultimately result in increased formation of harmful byproducts such as lactate or ammonia (Alden et al, 2020;Morris et al, 2020;Park, Reimonn, Agarabi, Brorson, & Yoon, 2018;Pereira, Kildegaard, & Andersen, 2018). Alternatively, supplementing amino acids in a time-dependent manner based on cell demand would ensure optimal consumption and cellular metabolism presumably resulting in better cell growth and mAb productivity.…”