earticle

영어

Glycan modifications of therapeutic glycoproteins influence on pharmacological functions including efficacy, safety, and biological activity. MS-based analytical tools for N-glycan chracterization have been intensively developed and now N-glycans including various variants (O-Acetylation, mannose-phosphates, and polylactosamines) on biotherapeutics are readily identified. However, there are few studies for the characterization of O-glycans because of the absence of analytical platform. Here, we have characterized novel O-glycosylation on therapeutic factor IX using nanoLC/MS and tandem MS. Interestingly, we could determine O-fucosylation and O-glucosylation as well as typical O-glycosylation having a core 1. Using tandem MS, we found that O-fucosylated glycans consisted of Fuc, GlcNAc, and Gal w/wo NeuAc while O-glucosylated glycans included Glc, Xyl, and Hex w/wo NeuAc. In addition the O-glycopeptide analysis showed that O-glucosylation and O-fucosylation were present at specific O-glycosylation sites of growth factor domain, respectively 53Ser and 61Ser. In previous studies the O-fucosylation of growth factor domain was known as an important factor to modulate signal transduction by the interaction with other proteins. Thus this study on the identification of O-glycan modifications could be useful for proving the correlation between glycosylation and drug efficacy.