title: Heterogeneity of recombinant antibodies: linking structure to function.
abstract: Structural heterogeneity of recombinant IgG1 antibodies derives from variations in conserved as well as unique structural features. Common sources of heterogeneity include Fc glycosylation, partial heavy chain C-terminal Lys processing, Fc methionine oxidation, hinge-region cleavage, and the glycation of Lys residues. Aspartate residues that are isomerized to iso-aspartate were detected by cation exchange or hydrophobic interaction chromatography for trastuzumab and omalizumab, respectively. Unpaired cysteines were detected in omalizumab using Ellman's reagent, with the thiol-containing Fab resolved using hydrophobic interaction chromatography after papain digestion. Structural variations that cause chromatographic resolution may indicate the presence of a form with reduced potency.
authors.affiliation: Analytical Chemistry Department, Genentech, Inc, South San Francisco, CA 94080, USA. reed@gene.com
authors.forename: R J
authors.initials: RJ
authors.lastname: Harris
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal / Q000032:analysis* / Q000737:chemistry; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis* / Q000737:chemistry; D000069444:Omalizumab; D046188:Protein Modification, Translational; D011499:Protein Processing, Post-Translational; D013329:Structure-Activity Relationship; D000068878:Trastuzumab
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D007074:Immunoglobulin G; D000069444:Omalizumab; D000068878:Trastuzumab