文献类型：期刊文献

英文题名：Elucidating the effects of pH shift on IgG1 monoclonal antibody acidic charge variant levels in Chinese hamster ovary cell cultures

作者：Xie, Panpan[1];Niu, Huijie[1];Chen, Xinning[1];Zhang, Xintao[1];Miao, Shiwei[2];Deng, Xiancun[2];Liu, Xuping[1];Tan, Wen-Song[1];Zhou, Yan[1];Fan, Li[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Hisun Pharmaceut Hangzhou Co Ltd, Hangzhou 311404, Zhejiang, Peoples R China

年份：2016

卷号：100

期号：24

起止页码：10343

外文期刊名：APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

收录：;EI(收录号：20163202691936);WOS:【SCI-EXPANDED(收录号:WOS:000388955500009)】；

基金：This work was supported by the National Natural Science Foundation of China (Nos. 21206040 and 21406066).

语种：英文

外文关键词：Acidic charge variants; IgG1 monoclonal antibody; Disulfide bond reduction; Galactosylation; Deamination; Liquid chromatography mass spectrometry

摘要：Charge variants, especially acidic charge variants, in recombinant monoclonal antibodies are critical quality attributes, which can affect antibodies' properties in vitro and in vivo. Meanwhile, charge variants are cumulative effects of various post-translational modifications and chemical degradations on antibody. In this work, to investigate the effect of lowering culture pH in the stationary phase on acidic charge variant contents in fed-batch cultures and its mechanism, cell culture experiments in 2-L bioreactors were firstly performed to explore the changes in the charge distribution under the pH downshift condition using weak cation exchange chromatography. It is found that acidic charge variant contents were significantly decreased by pH downshift. Then, to reveal the mechanism by which the content of acidic charge variants is reduced under pH downshift condition, the variation of post-translational modifications and chemical degradations under the pH downshift condition was explored. Meanwhile, the structure of the acidic charge variants was characterized. Several analysis experiments including size exclusion chromatography, capillary electrophoresis-sodium dodecyl sulfate under non-reducing conditions, tryptic peptide map, and reduced antibody mass were applied in this study. The results show that the mechanism by which the content of acidic charge variants is reduced is that the contents of disulfide bond reduction, galactosylation, and asparagine deamination of the HC-N388 in the Fc domain were reduced by pH downshift.