Transcriptomic analysis reveals mode of action of butyric acid supplementation in an intensified CHO cell fed‐batch process

• Published in: Biotechnology and bioengineering Vol. 119; no. 9; pp. 2359 - 2373
• Main Authors: Schulze, Markus, Kumar, Yadhu, Rattay, Merle, Niemann, Julia, Wijffels, Rene H., Martens, Dirk E.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.09.2022
• Subjects: Biosynthesis; Butyric acid; Cell proliferation; CHO cell culture; Gene regulation; Histones; IgG antibody; Immunoglobulin G; intensified fed‐batch; Intermediates; Mode of action; mRNA; N‐1 perfusion; Optimization; Process intensification; Protein biosynthesis; Quality management; RNA processing; RNA transport; rRNA; Supplements; Transcriptomics; Intensified fed-batch; Process intensification; CHO cell culture; Transcriptomics; Butyric acid; N-1 perfusion
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.28150

Process intensification is increasingly used in the mammalian biomanufacturing industry. The key driver of this trend is the need for more efficient and flexible production strategies to cope with the increased demand for biotherapeutics predicted in the next years. Therefore, such intensified production strategies should be designed, established, and characterized. We established a CHO cell process consisting of an intensified fed‐batch (iFB), which is inoculated by an N‐1 perfusion process that reaches high cell concentrations (100 × 106 c ml−1). We investigated the impact of butyric acid (BA) supplementation in this iFB process. Most prominently, higher cellular productivities of more than 33% were achieved, thus 3.5 g L−1 of immunoglobulin G (IgG) was produced in 6.5 days. Impacts on critical product quality attributes were small. To understand the biological mechanisms of BA in the iFB process, we performed a detailed transcriptomic analysis. Affected gene sets reflected concurrent inhibition of cell proliferation and impact on histone modification. These translate into subsequently enhanced mechanisms of protein biosynthesis: enriched regulation of transcription, messenger RNA processing and transport, ribosomal translation, and cellular trafficking of IgG intermediates. Furthermore, we identified mutual tackling points for optimization by gene engineering. The presented strategy can contribute to meet future requirements in the continuously demanding field of biotherapeutics production.