A feed enrichment strategy targeting the tricarboxylic acid cycle for increasing monoclonal antibody production and alleviating ammonia accumulation in Chinese hamster ovary cell culture

In this study, we demonstrated a simple strategy for increasing mAb production by enriching an existing feed with TCA cycle intermediates and precursors. TCA cycle intermediates/precursors were tested individually and as mixtures, termed as 'Enriched Feeds'. The enriched feed mixtures were tested in two compositions comprising: (i) only TCA intermediates/precursors that individually increased mAb titre (EF_Partial) and, (ii) all TCA in-termediates/precursors (EF_Complete). These mixtures were also tested for initiation at two phases: (i) from Day 3 (start of exponential phase) and, (ii) from Day 6 (start of stationary phase), and at two concentration levels (high and low). Our results showed that the EF_Partial mixtures were more efficient in increasing mAb titre as compared to the EF_Complete mixtures. The EF_Partial_D6_Low mixture gave the highest titre increase of 55 %, as compared to the control culture. Additionally, a decrease in ammonia production was observed immediately upon the supply of the enriched feeds. In the individual assessment, succinate supplementation resulted in a superior cell growth profile and also exhibited the most significant reduction in ammonia. The individually tested TCA compounds and mixtures also did not impact mAb quality. Therefore, in this study, we demonstrate that a simple approach of enriching feeds with TCA cycle intermediates/precursors effectively increases mAb pro-duction by > 50 % without affecting quality attributes.