title: The way forward, enhanced characterization of therapeutic antibody glycosylation: comparison of three level mass spectrometry-based strategies.
abstract: Glycosylation which plays a crucial role in the pharmacological properties of therapeutic monoclonal antibodies (MAbs) is influenced by several factors like production systems, selected clonal population and manufacturing processes. Efficient analytical methods are therefore required in order to characterize glycosylation at different stages of MAbs discovery and production. Three mass spectrometry (MS)-based strategies were compared to analyze N-glycosylation of MAbs either expressed in murine myeloma (NS0) or Chinese Hamster Ovary (CHO) cell lines, the two current main production systems used for therapeutic MAbs. First a top-down approach was used on intact and reduced MAbs by liquid chromatography coupled to an electrospray ionization-time of flight mass spectrometer (LC-ESI-TOF), which provided fast and accurate profiles of MAbs glycosylation patterns for routine controls. Secondly, after digestion of the antibody with the peptide N-glycosidase F (PNGase F) enzyme, released N-linked glycans were directly analyzed by electrospray ionization-tandem mass spectrometry (ESI-MS/MS) without any prior derivatization, which gave precise details on the structure of the most abundant glycoforms. Finally, a bottom-up approach on tryptic glycopeptides using a nanoLC-Chip-MS/MS ion trap (IT) system equipped with a graphitized carbon column was investigated. Data were compared to those obtained with a more classical C18 reversed phase column showing that this last method is well suited to detect low abundant glycoforms and to provide in one shot information regarding both the oligosaccharide structure and the amino acid sequence of its peptide moiety.
authors.affiliation: Centre d'Immunologie Pierre Fabre, 5 Avenue Napoléon III, 74160 Saint-Julien-en-Genevois, France. elsa.wagner@pierre-fabre.com
authors.forename: Elsa
authors.initials: E
authors.lastname: Wagner-Rousset
authors.forename: Audrey
authors.initials: A
authors.lastname: Bednarczyk
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Bussat
authors.forename: Olivier
authors.initials: O
authors.lastname: Colas
authors.forename: Nathalie
authors.initials: N
authors.lastname: Corvaïa
authors.forename: Christine
authors.initials: C
authors.lastname: Schaeffer
authors.forename: Alain
authors.initials: A
authors.lastname: Van Dorsselaer
authors.forename: Alain
authors.initials: A
authors.lastname: Beck
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000378:metabolism*; D016466:CHO Cells; D002853:Chromatography, Liquid; D006224:Cricetinae; D003412:Cricetulus; D006031:Glycosylation; D013058:Mass Spectrometry / Q000379:methods*; D010449:Peptide Mapping
chemical_list: D000911:Antibodies, Monoclonal