Yao Grace, Aron Kathryn, Borys Michael, Li Zhengjian, Pendse Girish, Lee Kyongbum
Bristol Myers Squibb, Biologics Development, Devens, MA 01434, USA.
Department of Chemical and Biological Engineering, Tufts University, Medford, MA 02155, USA.
Metabolites. 2021 Nov 30;11(12):823. doi: 10.3390/metabo11120823.
Much progress has been made in improving the viable cell density of bioreactor cultures in monoclonal antibody production from Chinese hamster ovary (CHO) cells; however, specific productivity (qP) has not been increased to the same degree. In this work, we analyzed a library of 24 antibody-expressing CHO cell clones to identify metabolites that positively associate with qP and could be used for clone selection or medium supplementation. An initial library of 12 clones, each producing one of two antibodies, was analyzed using untargeted LC-MS experiments. Metabolic model-based annotation followed by correlation analysis detected 73 metabolites that significantly correlated with growth, qP, or both. Of these, metabolites in the alanine, aspartate, and glutamate metabolism pathway, and the TCA cycle showed the strongest association with qP. To evaluate whether these metabolites could be used as indicators to identify clones with potential for high productivity, we performed targeted LC-MS experiments on a second library of 12 clones expressing a third antibody. These experiments found that aspartate and cystine were positively correlated with qP, confirming the results from untargeted analysis. To investigate whether qP correlated metabolites reflected endogenous metabolic activity beneficial for productivity, several of these metabolites were tested as medium additives during cell culture. Medium supplementation with citrate improved qP by up to 490% and more than doubled the titer. Together, these studies demonstrate the potential for using metabolomics to discover novel metabolite additives that yield higher volumetric productivity in biologics production processes.
在提高中国仓鼠卵巢（CHO）细胞单克隆抗体生产中生物反应器培养物的活细胞密度方面已取得了很大进展；然而，比生产率（qP）并未提高到相同程度。在这项工作中，我们分析了一个包含24个表达抗体的CHO细胞克隆的文库，以鉴定与qP呈正相关且可用于克隆选择或培养基补充的代谢物。使用非靶向液相色谱 - 质谱实验分析了一个初始文库，其中包含12个克隆，每个克隆产生两种抗体中的一种。基于代谢模型的注释以及相关性分析检测到73种与生长、qP或两者均显著相关的代谢物。其中，丙氨酸、天冬氨酸和谷氨酸代谢途径以及三羧酸循环中的代谢物与qP的关联最强。为了评估这些代谢物是否可用作鉴定具有高生产率潜力克隆的指标，我们对表达第三种抗体的12个克隆的第二个文库进行了靶向液相色谱 - 质谱实验。这些实验发现天冬氨酸和胱氨酸与qP呈正相关，证实了非靶向分析的结果。为了研究与qP相关的代谢物是否反映了对生产率有益的内源性代谢活性，在细胞培养过程中对其中几种代谢物作为培养基添加剂进行了测试。添加柠檬酸盐的培养基使qP提高了高达490%，并使滴度增加了一倍多。总之，这些研究证明了利用代谢组学发现新型代谢物添加剂的潜力，这些添加剂可在生物制品生产过程中提高体积生产率。
