Glycosylation is one of the most common and functionally important post-translational modifications (PTM) that proteins experience. Each protein molecule with the same sequence of amino acids may be glycosylated in a different location or a different way. The most common glycoforms are well understood and are referred to by the number of terminal galactose residues and presence of fucose – (e.g. G2F is a Glycoform with 2 terminal galactose residues, and with a Fucosylated biantennary complex). The relative abundance of G0, G0F, G1, G1F, G2, G2F, etc. in a sample is referred to as the glycan profile. To determine the glycan profile and glycan sites, two types of experiment can be performed:

1. To determine the location of the glycosylation sites and to measure the glycan profile at a specific location, we digest the protein resulting in glycopeptides. Comparing the glycopeptides back to the amino acid sequence reveals the glycan sites, and comparing their peak areas reveals the glycan profile.

2. Measure the mass of the glycoproteins using liquid chromatography coupled with mass spectrometry to record the peak area for each glycoform. For antibodies, we can also digest with specific enzymes to analyze the regions (e.g. Fc and Fab) separately and derive the glycan profile at the subunit level.

Applications of Our Glycan Analysis Service

Glycan analysis can be used to understand a valuable research reagent, a wild type antibody, a recombinantly expressed antibody, or a marketed therapeutic. Glycan information, along with other biophysical characteristics can aid in selection and engineering of antibodies for therapeutics, IVD reagents, controls and research reagents. It can also be used to understand how glycosylation is applied by different expression systems, cell pools, cell lines and production conditions. This informs early decisions in production and is part of quality control and ICH Q6B standards.

The Rapid Advantage.