(579d) Dynamic Regulation of Mitochondrial Metabolism As a Strategy to Maximize Mab Production in Industrial CHO Cell Cultures

The use of monoclonal antibodies (mAbs) has increased significantly in recent years, particularly in the treatment of cancer and asthma. Chinese hamster ovary (CHO) host cells are commonly used to produce mAbs, with about 80% of those approved on the market being generated by these cells. To meet the rising demand for mAbs and reduce production costs, increasing mAb titers and cell-specific productivity (qP) is necessary. Our lab has previously shown that high-producing CHO cell lines exhibit elevated metabolic activity in the mitochondrial TCA cycle. In particular, overexpressing an endogenous regulator that promotes mitochondrial metabolism increased mAb titer and qP but also attenuated cell growth compared to the parental line. This study aims to engineer CHO metabolism to promote mitochondrial respiration and TCA cycle flux specifically during the stationary phase, in order to minimize negative impacts on culture growth during exponential phase. Here, we hypothesized that overexpressing a mitochondrial regulatory gene at the onset of stationary phase would promote maximal qP while enabling the culture to reach high VCDs during growth phase. According to our previous study, if growth attenuation was caused by constitutive activation of mitochondrial metabolism, inducing transgene overexpression during the stationary phase should alleviate it. Our work uses an engineered cumate-inducible transposon system to generate stable cell lines by integrating foreign DNA into the CHO genome. A key objective of this study is to demonstrate the application of host cell engineering to increase metabolic efficiency of mammalian cell lines used in biomanufacturing.