C-terminal modification of monoclonal antibody drugs: Amidated species as a general product-related substance

• Published in: International journal of biological macromolecules Vol. 52; pp. 139 - 147
• Main Authors: Tsubaki, Masahiro, Terashima, Isamu, Kamata, Kunihiro, Koga, Akiko
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2013
• Subjects: animal ovaries; Animals; Antibodies, Monoclonal - biosynthesis; Antibodies, Monoclonal - chemistry; C-terminal processing; Chinese hamsters; CHO Cells; Cricetinae; Cricetulus; drugs; Humans; immunoglobulin G; Immunoglobulin G - biosynthesis; Immunoglobulin G - chemistry; in vitro studies; manufacturing; monoclonal antibodies; Monoclonal antibody; Peptide mapping; Peptidylglycine alpha-amidating monooxygenase; Protein Processing, Post-Translational; Protein Structure, Tertiary; Recombinant Proteins - biosynthesis; Recombinant Proteins - chemistry; Reversed phase-high performance liquid chromatography/mass spectrometry; Reversed phase-high performance liquid chromatography/mass spectrometry; Monoclonal antibody; C-terminal processing; Peptidylglycine alpha-amidating monooxygenase; Peptide mapping
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2012.09.016

Twelve therapeutic mAbs, comprising 10 IgG1s and 2 IgG4s, were analyzed by a peptide mapping technique to detect and quantify C-terminal modifications. C-terminal amidated structures were found in 8 out of the 12 mAbs. An in vitro study using a commercially available peptidylglycine alpha-amidating monooxygenase (PAM) revealed that both IgG1 and IgG4 can be substrates for PAM. This study showed that C-terminal amidation is a general C-terminal modification on the heavy chains of therapeutic mAbs and that C-terminal amidation of mAbs can be catalyzed by a certain PAM(s) in the Chinese hamster ovary (CHO) cells that are widely used for manufacturing therapeutic mAbs.