Screening and Characterization of Sialic Acid-Binding Variable Lymphocyte Receptors from Hagfish

Sialic acid is a diverse group of monosaccharides often found on the termini of <i>N</i>- and <i>O</i>-linked glycans as well as being components of glycoconjugates. Hypersialylation has been associated with the progression of chronic inflammation-mediated diseases such as ca...

Full description

Saved in:
Bibliographic Details
Main Authors: Mark Rickard N. Angelia, Abigail Joy D. Rodelas-Angelia, Cheolung Yang, Sojeong Park, Seung pyo Jeong, Hyeok Jang, Dennis Berbulla Bela-ong, Hobin Jang, Kim D. Thompson, Taesung Jung
Format: Article
Language:English
Published: MDPI AG 2024-11-01
Series:BioTech
Subjects:
Online Access:https://www.mdpi.com/2673-6284/13/4/46
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Sialic acid is a diverse group of monosaccharides often found on the termini of <i>N</i>- and <i>O</i>-linked glycans as well as being components of glycoconjugates. Hypersialylation has been associated with the progression of chronic inflammation-mediated diseases such as cardiovascular disease and cancer. Given its role in infection and disease-related processes, sialic acid is a promising target for therapeutic approaches that utilize carbohydrate-binding molecules. In this study, we screened for sialic acid-recognizing variable lymphocyte receptors (VLRBs) or ccombodies from inshore hagfish (<i>Eptatretus burgeri</i>) using a synthetic Neu5Ac-glycoconjugate as an antigen in immunoassay. Resulting ccombodies, 2D8, 5G11, 4A1, and 5F8 were further characterized in terms of their binding activity and specificity. A competitive ELISA using free haptens showed strong inhibition using either <i>N</i>-acetylneuraminic acid (Neu5Ac) and <i>N</i>-glycolylneuraminic acid (Neu5Gc). The half-maximal inhibitory concentrations (IC<sub>50</sub>) for Neu5Ac ranged from 7.02 to 17.06 mM, with candidates 4A1 and 5G11 requiring the least and highest amounts, respectively. IC<sub>50</sub> values for Neu5Gc ranged from 8.12 to 13.91 mM, for 4A1 and 5G11, respectively. Candidate ccombodies also detected naturally occurring sialic acid from known sialoglycoproteins using a dot blot assay. Neu5Gc-5G11 and Neu5Ac-2D8 yielded the strongest and weakest docking interactions with affinity values of −5.9 kcal/mol and −4.9 kcal/mol, respectively. Hydrogen bonding and hydrophobic interactions were predicted to be the predominant noncovalent forces observed between the ccombodies and sialic acid. This study demonstrates that glycan-binding VLRBs from hagfish hold promise in augmenting the glycobiologists’ toolkit in investigating the roles of glycans in human and animal health and disease.
ISSN:2673-6284