Pfizer, Culture Process Development, 1 Burtt Road, Andover, MA 01810, USA.
Metab Eng. 2011 Jan;13(1):108-24. doi: 10.1016/j.ymben.2010.09.003. Epub 2010 Oct 7.
Fed-batch cultures are extensively used for the production of therapeutic proteins. However, process optimization is hampered by lack of quantitative models of mammalian cellular metabolism in these cultures. This paper presents a new kinetic model of CHO cell metabolism and a novel framework for simulating the dynamics of metabolic and biosynthetic pathways of these cells grown in fed-batch culture. The model defines a subset of the intracellular reactions with kinetic rate expressions based on extracellular metabolite concentrations and temperature- and redox-dependent regulatory variables. The simulation uses the rate expressions to calculate pseudo-steady state flux distributions and extracellular metabolite concentrations at discrete time points. Experimental data collected in this study for several different CHO cell fed-batch cultures are used to derive the rate expressions, fit the parameters, and validate the model. The simulations accurately predicted the effects of process variables, including temperature shift, seed density, specific productivity, and nutrient concentrations.
分批补料培养广泛用于治疗性蛋白的生产。然而，由于缺乏这些培养物中哺乳动物细胞代谢的定量模型，因此阻碍了工艺优化。本文提出了 CHO 细胞代谢的新动力学模型和一种新的框架，用于模拟在分批补料培养中生长的这些细胞的代谢和生物合成途径的动力学。该模型基于胞外代谢物浓度和温度及氧化还原相关的调节变量，定义了一组具有动力学速率表达式的细胞内反应。该模拟使用速率表达式在离散时间点计算准稳态通量分布和胞外代谢物浓度。本研究中为几种不同的 CHO 细胞分批补料培养收集的实验数据用于推导速率表达式、拟合参数和验证模型。模拟准确预测了工艺变量的影响，包括温度变化、接种密度、比生产率和营养浓度。
