Becker Max, Junghans Lisa, Teleki Attila, Bechmann Jan, Takors Ralf
Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany.
Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany.
Front Bioeng Biotechnol. 2019 Apr 11;7:76. doi: 10.3389/fbioe.2019.00076. eCollection 2019.
Biopharmaceutical production processes strive for the optimization of economic efficiency. Among others, the maximization of volumetric productivity is a key criterion. Typical parameters such as partial pressure of CO (pCO) and pH are known to influence the performance although reasons are not yet fully elucidated. In this study the effects of pCO and pH shifts on the phenotypic performance were linked to metabolic and energetic changes. Short peak performance of q (23 pg/cell/day) was achieved by early pCO shifts up to 200 mbar but followed by declining intracellular ATP levels to 2.5 fmol/cell and 80% increase of q. On the contrary, steadily rising q could be installed by slight pH down-shifts ensuring constant cell specific ATP production (q) of 27 pmol/cell/day and high intracellular ATP levels of about 4 fmol/cell. As a result, maximum productivity was achieved combining highest q (20 pg/cell/day) with maximum cell density and no lactate formation. Our results indicate that the energy availability in form of intracellular ATP is crucial for maintaining antibody synthesis and reacts sensitive to pCO and pH-process parameters typically responsible for inhomogeneities after scaling up.
生物制药生产过程致力于实现经济效率的优化。其中，体积生产率的最大化是一个关键标准。虽然原因尚未完全阐明，但已知诸如一氧化碳分压（pCO）和pH等典型参数会影响性能。在本研究中，pCO和pH变化对表型性能的影响与代谢和能量变化相关联。通过早期将pCO升高至200毫巴实现了q的短峰性能（23皮克/细胞/天），但随后细胞内ATP水平降至2.5飞摩尔/细胞，q增加了80%。相反，通过轻微的pH下降可实现q的稳步上升，确保细胞比ATP产量（q）恒定为27皮摩尔/细胞/天，细胞内ATP水平约为4飞摩尔/细胞。结果，结合最高的q（20皮克/细胞/天）、最大细胞密度且无乳酸形成，实现了最大生产率。我们的结果表明，细胞内ATP形式的能量可用性对于维持抗体合成至关重要，并且对pCO和pH等工艺参数敏感，这些参数通常是放大后不均匀性的原因。
