Analysis of O-Acetylated Sialic Acids in Dried Blood Spots

Abstract

Sialic acid is a family of N-and O-substitutions of neuraminic acid. Plasma or serum sialic acid has been established as a potential disease marker. For example, the presence of 9-O-acetyl on the sialic acid of some glycans and glycoconjugates (e.g., 9-O-acetyl GD3 ganglioside) could be related to cancer occurrence. A variety of assays are available to measure serum or plasma sialic acid; however, sample preparation and storage can alter the O-acetylation profile due to the loss of O-acetyl groups and/or the migration of Oacetyl groups. Herein, we report dried blood spot (DBS) sampling, in combination with diamino-4,5-methylenedioxybenzene derivatization, for profiling sialic acids in blood samples with minimal alteration in O-acetylation patterns. The feasibility of the method was first evaluated by analyzing sialic acids in crucian carp blood and comparing with traditional blood/ plasma sample preparation procedures. A total of 19 different sialic acids were identified by using liquid chromatography− Orbitrap mass spectrometry, including four mono-O-acetylated N-acetylneuraminic acids, four mono-O-acetylated Nglycolylneuraminic acids, six di-O-acetylated N-acetylneuraminic acids, and three tri-O-acetylated N-acetylneuraminic acids. The long-term storage study indicated that DBS sampling could effectively preserve the O-acetylation information for at least 6 weeks. Thus, it is demonstrated that this method is a valuable tool for the study of sialic acid diversity, especially for the characterization of isomeric structures.

Tilapia Lake Virus Does Not Hemagglutinate Avian and Piscine Erythrocytes and NH4Cl Does Not Inhibit Viral Replication In Vitro

“…Other viruses that use the Neu5,9Ac 2 receptor include coronaviruses. This receptor has been reported in various species, such as humans, rabbits, rats, guinea pigs, horses, chicken, turkey, goose, salmonids, crucian carp, mollusks, and sea urchins [40][41][42][43][44][45][46][47][48][49][50]. Unlike influenza C, ISAV specifically binds Neu4,5Ac 2 glycans on host cells using its hemagglutinin-esterase (HE) protein.…”

Development and Characterization of Fluorescent Mannose and Sialic Acid Based Chemical Probes for Lectin Discovery and Enzyme Studies

“…39 Further structural diversity of these core sialic acid members can be generated by modification of their hydroxyl groups at C-4, C-7, C-8, and C-9 with O-acetyl, O-methyl, O-sulfate, O-lactyl, or phosphate substituents. 36,40,41 Besides their structural diversity, they are notably diverse in their glycosidic linkages, fundamental glycan chains and their exposed location. 42 Given their remarkable diversity, it is not surprising that they are involved in several biological roles, including regulation of solubility, stability and half-lives of secreted proteins, act as cellular receptors for influenza viruses, and ligands during cell-cell interactions and cell-molecule recognition.…”

“…42 Given their remarkable diversity, it is not surprising that they are involved in several biological roles, including regulation of solubility, stability and half-lives of secreted proteins, act as cellular receptors for influenza viruses, and ligands during cell-cell interactions and cell-molecule recognition. 41,42,43 For instance, non-sialylated glycoforms have been shown to exhibit drastically shorter in-vivo half-lives compared to their sialylated equivalents. 44 Increasing the amount of sialic acid residues of therapeutic glycoprotein boosts in-vivo half-life.…”

Assays for the identification and quantification of sialic acids: Challenges, opportunities and future perspectives

“…This has been put to good use in analysing the Oacetylated derivatives present in dried blood spots by DMB analysis. 83 The usage is limited to identification of sialic acids however and separate synthesis or extraction of O-acetylated derivatives from biological samples is required for accurate quantitation.…”