Metabolomic characterization of monoclonal antibody-producing Chinese hamster lung (CHL)-YN cells in glucose-controlled serum-free fed-batch operation

The fast-growing Chinese hamster lung (CHL)-YN cell line was recently developed for monoclonal antibody production. In this study, we applied a serum-free fed-batch cultivation process to immunoglobulin (Ig)G1-producing CHL-YN cells, which were then used to design a dynamic glucose supply system to stabilize the extracellular glucose concentration based on glucose consumption. Glucose consumption of the cultures rapidly oscillated following three phases of glutamine metabolism: consumption, production, and re-consumption. Use of the dynamic glucose supply prolonged the viability of the CHL-YN-IgG1 cell cultures and increased IgG1 production. Liquid chromatography with tandem mass spectrometry-based target metabolomics analysis of the extracellular metabolites during the first glutamine shift was conducted to search for depleted compounds. The results suggest that the levels of four amino acids, namely arginine, aspartate, methionine, and serine, were sharply decreased in CHL-YN cells during glutamine production. Supporting evidence from metabolic and gene expression analyses also suggest that CHL-YN cells acquired ornithine- and cystathionine-production abilities that differed from those in Chinese hamster ovary-K1 cells, potentially leading to proline and cysteine biosynthesis. The authors applied a novel fast-proliferating cell line, Chinese hamster lung (CHL)-YN, to the monoclonal antibody production by developing glucose control strategies for serum-free fed-batch cultivation and then studying their metabolic profiles. Glucose feeding design associated with the fluctuation of glutamine metabolism could stabilize extracellular glucose concentration and advantage in cell survivability. Additionally, the metabolomics analyses disclosed the exclusive metabolic profiles of CHL-YN cells compared to Chinese hamster ovary (CHO)-K1 cells, which potentially indicate their proline and cysteine biosynthetic capabilities. image