Glycoproteins are a group of proteins with oligosaccharide chains or glycans covalently attached to amino acid side-chains. These proteins are ubiquitously distributed and play an important role in various biological processes, such as cell signaling, cell-cell interaction, immune recognition, cell proliferation, and differentiation. Therefore, the alterations of glycoproteins possess a close relationship with the progression of diseases, such as autoimmune disease, Alzheimer’s disease, and cancer.

https://www.creative-biolabs.com/glycoprotein/glycoprotein-biomarkers-research.htm