(642b) 13C Flux Analysis of CHO Cell Metabolism Over Entire Cell Culture Phase for Recombinant Protein Production

Chinese Hamster Ovary (CHO) cells cultures are the major source of production for human therapeutic proteins. Often the goal of such a cell culture is to separate the growth phase of the cells, from the non growth phase where ideally the cells are diverting resources to produce the protein of interest. Thus it is imperative to understand biochemical fluxes inside CHO cells as a function of culture conditions and their growth phase. 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. Analysis of the glycolytic pathway and pentose phosphate pathway (PPP) indicated that almost all of the glucose is diverted towards PPP with a high NADPH production; with recycle from PPP to G6P in some cases. Almost all of the pyruvate produced from glycolysis entered the TCA cycle with little or no lactate production. Here we compare culture conditions for a transgenic CHO cell line and perform comparative flux analysis over the cell culture time course to provide insights into flux change during the transition of the cell culture phase.