(130d) Metabolic Flux Analysis and Proteomics of CHO Cell Culture During Growth and Recombinant Protein Production

Chinese Hamster Ovary (CHO) cells cultures are the major source of production for human therapeutic proteins. The cell culture process can dramatically influence the cell culture performance, including cell growth, protein yield and quality. We have previously reported the flux analysis of CHO cells in non growth phase. Fluxes under two different process conditions, fed with a mixture of 1-¹³C and U-¹³C glucose were evaluated using isotopomer modeling. We perform comparative flux analysis for the two process conditions over the entire cell culture time course to provide insights into flux changes. Analysis of the glycolytic pathway and pentose phosphate pathway (PPP) indicated that the percentage of glucose diverted towards PPP increases with the progression of cell culture. Around the pyruvate node, the lactic acid production was highest during the growth phase of the cell culture, and decreased as the cell culture progressed. Later, it changed to lactate consumption around mid stationary phase, but then drastically changed to lactate excretion during the death phase. An untargeted proteomic analysis is also being performed to understand the causes of the underlying shifts in these fluxes.