Mass Spectrometry Analysis of Biotherapeutic Monoclonal Antibody Glycosylation

Glycosylation plays a critical role in the efficacy of therapeutic monoclonal antibodies (mAbs), the major category of glycoprotein-based therapeutic medicines. It is claimed that glycosylation of therapeutic mAbs has implications on their half-life, immunogenicity, and pharmacokinetics. Comprehensive characterization of glycosylation enables a deeper understanding of the complexity of therapeutic mAbs. The method presented here describes an integrated approach that incorporates filtered-aided sample preparation, mass spectrometry with different ion activation techniques, and a software that enables intact glycopeptide database search and de novo sequencing, to provide both N- and O-linked glycan profiling with structural resolution, without performing pre-glycoprotein/glycopeptide enrichment.