Erklavec Zajec Vivian, Novak Uroš, Kastelic Miha, Japelj Boštjan, Lah Ljerka, Pohar Andrej, Likozar Blaž
Department of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Ljubljana, Slovenia.
Novartis, Lek Pharmaceuticals d.d., Mengeš, Slovenia.
Biotechnol Bioeng. 2021 Jan;118(1):397-411. doi: 10.1002/bit.27578. Epub 2020 Oct 11.
Experimental and modeling work, described in this article, is focused on the metabolic pathway of Chinese hamster ovary (CHO) cells, which are the preferred expression system for monoclonal antibody protein production. CHO cells are one of the primary hosts for monoclonal antibodies production, which have extensive applications in multiple fields like biochemistry, biology and medicine. Here, an approach to explain cellular metabolism with in silico modeling of a microkinetic reaction network is presented and validated with unique experimental results. Experimental data of 25 different fed-batch bioprocesses included the variation of multiple process parameters, such as pH, agitation speed, oxygen and CO content, and dissolved oxygen. A total of 151 metabolites were involved in our proposed metabolic network, which consisted of 132 chemical reactions that describe the reaction pathways, and include 25 reactions describing N-glycosylation and additional reactions for the accumulation of the produced glycoforms. Additional eight reactions are considered for accumulation of the N-glycosylation products in the extracellular environment and one reaction to correlate cell degradation. The following pathways were considered: glycolysis, pentose phosphate pathway, nucleotide synthesis, tricarboxylic acid cycle, lipid synthesis, protein synthesis, biomass production, anaplerotic reactions, and membrane transport. With the applied modeling procedure, different operational scenarios and fed-batch techniques can be tested.
本文所述的实验和建模工作聚焦于中国仓鼠卵巢(CHO)细胞的代谢途径,CHO细胞是单克隆抗体蛋白生产的首选表达系统。CHO细胞是单克隆抗体生产的主要宿主之一,在生物化学、生物学和医学等多个领域有广泛应用。在此,提出了一种通过微动力学反应网络的计算机模拟来解释细胞代谢的方法,并通过独特的实验结果进行了验证。25种不同补料分批生物过程的实验数据包括多个过程参数的变化,如pH值、搅拌速度、氧气和二氧化碳含量以及溶解氧。我们提出的代谢网络共涉及151种代谢物,由132个描述反应途径的化学反应组成,包括25个描述N-糖基化的反应以及产生的糖型积累的其他反应。另外考虑了8个反应用于N-糖基化产物在细胞外环境中的积累以及1个与细胞降解相关的反应。考虑了以下途径:糖酵解、磷酸戊糖途径、核苷酸合成、三羧酸循环、脂质合成、蛋白质合成、生物量生产、回补反应和膜转运。通过应用的建模程序,可以测试不同的操作场景和补料分批技术。