[1S06a] 15. Advanced Cell and Cell Culture Engineering for Biopharmaceuticals and Functional Food - Part 2

3:20 PM - 3:40 PM JST(6:20 AM - 6:40 AM UTC)

[1ACCE-09] Flux balance analysis of cellular metabolism for CHL-YN cells by genome-scale metabolic models

○Masahiro Yamazaki^1,2,3, Hirotaka Kuroda², Kazuya Sorada^1,2,3, Yoshihiro Toya⁴, Hiroshi Shimizu⁴, Noriko Yamano-Adachi¹, Takeshi Omasa¹ (1. Grad. Sch. Eng., UOsaka. (Japan), 2. Shimadzu Corp. (Japan), 3. Shimadzu Analytical Innovation Research Lab., UOsaka. (Japan), 4. Grad. Sch. IST., UOsaka. (Japan))

Keywords:

Flux balance analysis,Genome-scale metabolic model,Chinese hamster lung cells,Chinese hamster ovary cells

Chinese hamster lung (CHL)-YN cells proliferate approximately twice as fast as Chinese hamster ovary (CHO) cells and are expected to serve as an alternative host cell for therapeutic antibody production. For industrial application of CHL-YN cells, it is required to proceed rationally with bioprocess development, including medium optimization, and it is important to better understand CHL-YN cell physiology. In this regard, flux balance analysis (FBA) using genome-scale metabolic models (GEMs) can mechanically describe cellular metabolic behavior under various culture conditions, and is useful for understanding metabolic behavior and identifying metabolic bottlenecks. The purpose of this study is to elucidate the metabolic behavior of CHL-YN cells by using GEMs. In this study, GEMs capable of describing CHL-YN cells metabolism were constructed. Under multiple media, FBA using constructed models was performed to systematically characterize CHL-YN cells metabolism. First, the cell dry weight (CDW) and the total protein content were measured, and the biomass equation was set up. CHL-YN cells showed the lower CDW and total protein content than CHO cells, but their amino acid composition was similar. The defined biomass equation and transcriptome data were incorporated into CHO-GEM (iCHO2291) to reconstruct specific cell line models. Next, to characterize phenotype and metabolic behavior, batch cultures of CHL-YN cells and CHO-K1 cells under multiple media were performed. Using reconstructed models, intracellular metabolic fluxes were predicted by incorporating enzyme kinetic parameters, growth rates, IgG1 specific productivity, and experimentally measured uptake/secretion rates. CHL-YN cells showed approximately twice the growth rate of CHO-K1 cells under all conditions. CHL-YN cells also showed higher fluxes through glycolysis and the TCA cycle, promoting increased energy production. Consistent with the previous study, these results suggested that enhanced energy metabolism supports the rapid proliferation of CHL-YN cells. While CHL-YN cells showed rapid growth under all conditions, differences in phenotype and metabolic behavior were observed among the media. In CHO-K1 cells, growth rates correlated with glucose consumption rates and ATP production via glycolysis, with no major differences observed in mitochondrial energy metabolism. In contrast, CHL-YN cells showed differences not only in glycolysis but also in mitochondrial metabolism depending on the medium. Although CHL-YN cells exhibited the lowest glycolytic flux in the medium that supported the highest growth rate, the greatest ATP production and NAD/NADH turnover rates were observed in the mitochondria. In CHL-YN cells with an activated TCA cycle, the enhanced contribution of mitochondrial redox reactions may support rapid growth.