Antibody Drug Glycopeptide Analysis

Antibody drugs are a class of drugs that treat diseases through artificially synthesized antibodies, which achieve therapeutic purposes by specifically binding to target molecules. Common types of antibody drugs include monoclonal antibodies, artificially synthesized antibody fragments, immunotoxins, antibody-drug conjugates, etc. Antibody drugs have shown significant efficacy in the treatment of various diseases, such as cancer, autoimmune diseases, inflammatory diseases, immune regulation, and ophthalmic diseases.

 

Protein glycosylation is a common and highly important post-translational modification. It refers to the process by which certain sugars are transferred to specific amino acid residues on a protein to form glycosidic bonds, under the action of glycosyltransferases. Protein glycosylation significantly impacts the stability, efficacy, and immunogenicity of antibody drugs. For instance, the presence of sugars like OligoMan and Gal-a-1 can affect the immunogenicity or half-life of the drug. Therefore, in-depth research on protein glycosylation is crucial for the development and optimization of biologics, including antibody drugs. Glycopeptide analysis is a vital step in the structural analysis of glycosylation modifications in antibody drugs.

 

Glycopeptide analysis typically involves the enzymatic digestion of intact proteins using proteases, producing smaller peptides. These peptides are then separated by chromatography or electrophoresis and subsequently analyzed by MALDI-MS or ESI-MS mass spectrometry. Mass spectrometry at the glycopeptide level not only provides information on glycosylation sites but also allows for in-depth analysis of glycopeptide sequences, oligosaccharide composition, and more through tandem mass spectrometry.

 

MtoZ Biolabs utilizes the next-generation hybrid mass spectrometer Orbitrap Fusion, which features HCD/ETD "dual fragmentation modes," to analyze the intact glycopeptides of complex glycoproteins. Following this, we use Byonic software to interpret the raw mass spectrometry data, enabling the identification of N-glycosylation and O-glycosylation sites and the analysis of the glycan composition associated with these sites.