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bioRxiv · 10.1101/2024.04.25.591062

Discovery and characterization of unusual O-link glycosylation of IgG4 antibody using LC-MS

Janecki, D. J.·Kao-Scharf, C.-Y.·Hoffmann, A.
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Abstract

4The analysis of several batches of commercial biopharmaceutical product Dupixent using top-down intact mass spectrometry revealed that this immunoglobulin IgG4 features a small amount of O-link glycosylation in Fab region. This is the first report of an O-link glycosylation in IgG4 antibody. The paper describes most likely structure of the O-link glycosylation as well as probable location(s). The relative quantification showed only small quantity of the modification but appearing consistently in several batches of Dupixent. The O-link glycosylation site was characterized by standard tryptic peptide digestion and LC-MS analysis approach.

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Janecki, D. J., Kao-Scharf, C.-Y., Hoffmann, A.. 2024-04-26. Discovery and characterization of unusual O-link glycosylation of IgG4 antibody using LC-MS. https://doi.org/10.1101/2024.04.25.591062

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