Chinese hamster ovary cells are widely used in various biopharmaceutical industries as preferred host cells for the production of recombinant proteins. In an effort to increase yield and reduce production costs, the incorporation of small molecule additives into the culture medium has emerged as an effective approach to augment the expression of recombinant proteins, thus increasing overall efficiency. Here, we examined the impact of five small molecules on protein expression in CHO-engineered cell lines. These molecules included sodium valproate, alanyl-L-tyrosine, ascorbic acid, sodium citrate and ferrous sulphate. Their optimal concentrations were determined through univariate analysis aimed at enhancing cell growth and protein production. Our findings revealed that inoculating cells at a density of 1.0 × 10 6 cells/mL with the simultaneous addition of sodium valproate at a concentration of 2 mM for 0 h yielded the most favorable results. Notably, while valproate inhibited cell growth in a dose-dependent manner, it simultaneously extended cell culture longevity. Additionally, sodium valproate was observed to decrease glucose consumption, collectively increasing protein expression. In conclusion, our data suggest that sodium valproate is a potent chemical agent capable of increasing the production of recombinant protein in CHO cells. This enhancement is achieved by the modulation of metabolic pathways in CHO-engineered cell lines, thereby facilitating a state of low metabolism and high protein expression.
Wang Jiaqi,Wang Chen,Fan Li,Zhao Liang,Tan Wen-Song
Chinese hamster ovary (CHO) cells are predominant in the production of therapeutic proteins to treat various diseases. Characterization and investigation of CHO cell metabolism in a quick and simple way could boost process and cell line development. Therefore, a method to simultaneously detect seven redox- and energy-related metabolites in CHO cells by capillary electrophoresis has been developed. An on-line focusing technique was applied to improve the peak shape and resolution by using a 50 μm × 44 cm uncoated fused silica capillary. Key parameters and their interactions were investigated by design of experiments (DoE) and optimized conditions were determined by desirability function as follows: 24 °C, 95 mM, and pH 9.4 of BGE. The method was validated to ensure sensitivity, linearity, and reproducibility. The limits of detection (LODs) ranged from 0.050 to 0.688 mg/L for seven metabolites, and correlation coefficients of linearity were all greater than 0.996. The relative standard deviations (RSD) of migration time and peak area were smaller than 0.872% and 5.5%, respectively, except for NADPH, and the recoveries were between 97.5 and 101.2%. The method was successfully applied to analyze the extracts from CHO cells under two different culture conditions.
Graphical abstract
危险品化学品经营许可证（带存储）