LAUSR

ObjectiveTo explore the influence of ultra-low carbon dioxide partial pressure (pCO2) on the monoclonal antibody (mAb) N-glycosylation profile in Chinese hamster ovary (CHO) cell culture.ResultsIn fed-batch bioreactor cultures, lowering the pCO2 in the medium (< 25 mmHg) via increasing headspace aeration decreased the cell viability and mAb production in CHO cells. Additionally, mAb galactosylation under low pCO2 was approximately 27.45 ± 2.13%, noticeably higher than that observed under normal pCO2 (21.36 ± 1.66%) at harvest. However, all of the relevant intracellular nucleotide sugar concentrations were dramatically decreased to approximately 50% of the levels found under normal pCO2 on day 7. Real-time PCR revealed that the upregulation of galactosylation-related glycosyltransferase genes and substrate transporter genes played a critical role in the improved galactosylation under the ultra-low pCO2 condition.ConclusionsIn the bioreactor culture processes, ultra-low pCO2 demonstrated a positive effect on mAb galactosylation.