Glycobiomarkers focus on structural changes of glycans found in specific glycoproteins, which are linked to the onset or severity of various diseases. The technology to analyze glycans and to detect minor structural changes in glycans has made possible a new clinical test involving glycobiomarkers. This article introduces the current status of comprehensive analysis of glycobiomarkers for liver disease, and their use in analysis of glycans in fatty liver disease by our group.
In the fifth installment of this series, glycan databases will be described. Glycans with various structures exist in the body and they also take the form of free glycans and complex carbohydrates such as glycoproteins and glycolipids. The glycan databases described below include: the international glycan structure repository GlyTouCan for glycan structures; GlyCosmos Glycans for glycan structures; GlycomeAtlas for visualizing localization of glycomes; TotalGlycome for analyzing glycan expression data; and GlycoEpitope for carbohydrate antigens and antibodies.
Sugar chains play important roles in antibody function. It is well known that the deletion of a sugar chain from IgG increases the cytotoxic activity. It was also reported that sugar chain deletion from IgE, which is the main topic of this review, decreases the binding level to FcεR, which is the high-affinity receptor of IgE. However, an enzyme that specifically digests the sugar chain on IgE and affects the function has not yet been found. We previously reported that commercial receptor-destroying enzyme (RDE) from Vibrio cholerae specifically modulated the construction of murine IgE and inactivated the function. We also revealed that RDE modulated sugar chains on IgE. In our current study, we are evaluating the effect against human IgE. We hope to contribute to the development of a new treatment for allergy by modulating the sugar chain to inactivate IgE.
