Structure-Specific N- Glycoproteomics Characterization of NIST Monoclonal Antibody Reference Material 8671.

The characteristics of monoclonal antibodies (mAbs) cohering various function effectors show great expectation in therapy. Glycosylation, one of the common post-translational modifications, deeply influences cohesion. It is necessary to grasp monosaccharide composition/sequence and glycan structures in mAbs. There has been comprehensive mass spectrometry characterization of N- glycosylation of mAbs, and monosaccharide compositions are deduced according to known biosynthetic rules. Our recently developed intact N- glycopeptide search engine GPSeeker has made structure-specific characterization of N- glycosylation possible with structure-diagnostic fragment ions from selective fragmentation of N- glycan moieties. Here, we report our structure-specific N- glycoproteomics characterization of NIST monoclonal antibody reference material 8671 using GPSeeker, and 59 N- glycan structures (including 16 pairs of isomers) are characterized.