caa a22 4500 605498350 CHVBK 20210128100545.0 cr unu---uuuuu 210128e20150801xx s 000 0 eng 10.1007/s00253-015-6617-y doi (NATIONALLICENCE)springer-10.1007/s00253-015-6617-y Elucidating the effects of arginine and lysine on a monoclonal antibody C-terminal lysine variation in CHO cell cultures [Elektronische Daten] [Xintao Zhang, Hongping Tang, Ya-Ting Sun, Xuping Liu, Wen-Song Tan, Li Fan] C-terminal lysine variants are commonly observed in monoclonal antibodies (mAbs) and found sensitive to process conditions, especially specific components in culture medium. The potential roles of media arginine (Arg) and lysine (Lys) in mAb heavy chain C-terminal lysine processing were investigated by monitoring the lysine variant levels under various Arg and Lys concentrations. Both Arg and Lys were found to significantly affect lysine variant level. Specifically, lysine variant level increased from 18.7 to 31.8% when Arg and Lys concentrations were increased from 2 to 10mM. Since heterogeneity of C-terminal lysine residues is due to the varying degree of proteolysis by basic carboxypeptidases (Cps), enzyme (basic Cps) level, pH conditions, and product (Arg and Lys) inhibition, which potentially affect the enzymatic reaction, were investigated under various Arg and Lys conditions. Enzyme level and pH conditions were found not to account for the different lysine variant levels, which was evident from the minimal variation in transcription level and intracellular pH. On the other hand, product inhibition effect of Arg and Lys on basic Cps was evident from the notable intracellular and extracellular Arg and Lys concentrations comparable with Ki values (inhibition constant) of basic Cps and further confirmed by cell-free assays. Additionally, a kinetic study of lysine variant level during the cell culture process enabled further characterization of the C-terminal lysine processing. Springer-Verlag Berlin Heidelberg, 2015 Chinese hamster ovary cells nationallicence Monoclonal antibody nationallicence Lysine variant nationallicence Arginine nationallicence Lysine nationallicence Carboxypeptidase nationallicence Zhang Xintao The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Tang Hongping The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Sun Ya-Ting The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Liu Xuping The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Tan Wen-Song The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Fan Li The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/16(2015-08-01), 6643-6652 0175-7598 99:16<6643 2015 99 253 https://doi.org/10.1007/s00253-015-6617-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-015-6617-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zhang Xintao The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 700 1- Tang Hongping The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 700 1- Sun Ya-Ting The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 700 1- Liu Xuping The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 700 1- Tan Wen-Song The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 700 1- Fan Li The State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237, Shanghai, China aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/16(2015-08-01), 6643-6652 0175-7598 99:16<6643 2015 99 253