title: Charge variants characterization of a monoclonal antibody by ion exchange chromatography coupled on-line to native mass spectrometry: Case study after a long-term storage at +5°C.
abstract: Numerous putative post-translational modifications may induce variations of monoclonal antibodies charge distribution that can potentially affect their biological activity. The characterization and the monitoring of these charge variants are critical quality requirements to ensure stability and process consistency. Charge variants are usually characterized by preparative ion exchange chromatography, collection of fractions and subsequent reverse-phase liquid chromatography with mass spectrometry analysis. While this process can be automatized by on-line two-dimensional chromatography, it remains often complex and time consuming. For this reason, a straightforward on-line charge variant analysis method is highly desirable and analytical laboratories are actively pursuing efforts to overcome this challenge. In this study, a mixed mode ion exchange chromatographic method using volatile salts and coupled on-line to native mass spectrometry was developed in association with a middle-up approach for a detailed characterization of monoclonal antibodies charge variants. An aged monoclonal antibody, presenting a complex charge variant profile was successfully investigated by this methodology as a case study. Results demonstrate that deamidation of the heavy chain was the major degradation pathway after long-term storage at 5°C while oxidation was rather low. The method was also very useful to identify all the clipped forms of the antibody.
authors.affiliation: LFB Biotechnologies, 3 Avenue des Tropiques, 91958, Courtabœuf, Les Ulis, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Leblanc
authors.affiliation: LFB Biotechnologies, 3 Avenue des Tropiques, 91958, Courtabœuf, Les Ulis, France.
authors.forename: C
authors.initials: C
authors.lastname: Ramon
authors.affiliation: LFB Biotechnologies, 3 Avenue des Tropiques, 91958, Courtabœuf, Les Ulis, France.
authors.forename: N
authors.initials: N
authors.lastname: Bihoreau
authors.affiliation: LFB Biotechnologies, 3 Avenue des Tropiques, 91958, Courtabœuf, Les Ulis, France. Electronic address: chevreuxg@lfb.fr.
authors.forename: G
authors.initials: G
authors.lastname: Chevreux
mesh_terms: D000577:Amides / Q000737:chemistry; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D002850:Chromatography, Gel / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods*; D004356:Drug Storage; D007477:Ions / Q000737:chemistry; D010084:Oxidation-Reduction; D010449:Peptide Mapping / Q000379:methods; D055550:Protein Stability; D059748:Proteolysis; D055672:Static Electricity; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D000577:Amides; D000911:Antibodies, Monoclonal; D007477:Ions
keywords: Charge variants; Deamidation; IdeS; Ion exchange chromatography; Mass spectrometry; Monoclonal antibody