Prevention and rescue direction Prevention and rescue direction Approach examples References
Prevention Inhibit enzyme overexpression Knocked down the expression of thioredoxin (Trx) in CHO cells Koterba, Borgschulte, & Laird, 2012
Inhibit enzyme activity during cell culture and cell harvest
Induce Ethylenediaminetetraacetic acid (EDTA) to inhibit hexokinase activity and reduce the formation of glucose-6-P; Induce Cu2+, Zn2+, Hg2+ and Co2+ to inhibit Trx activity; Induce Aurothioglucose (ATG) and aurothiomalate (ATM) to inhibit thioredoxin reductase activity Kao, Hewitt, Trexler-Schmidt, & Laird, 2010; Trexler-Schmidt et al., 2010
Reduce enzyme amount for disulfide bond reduction during cell culture, cell harvest and clarified bulk (CB) storage
Induce O2, H2O2 and cysteine as enzyme competitors;
Du et al., 2018; Mun et al., 2015; Chung et al., 2017; Handlogten, Wang, & Ahuja, 2020
Control centrifuge force during harvest to minimize cell lysis; Control depth filtration pressure to minimize cell lysis;
Trexler-Schmidt et al., 2010; O’Mara et al., 2019
Slowdown enzyme reaction rate during cell harvest and CB storage Lower pH and temperature Xie et al., 2016; Hutterer et al., 2013; Liu, Nowak, Shao, Ponniah, & Neill, 2016
Reduce reaction time Shorten CB storage time Mun et al., 2015; O’Mara et al., 2019
Rescue Reoxidize reduced mAb during Protein A chromatography Introduce redox wash to reoxidize reduced mAb Tan et al., 2020; Tang et al., 2020