CD BioGlyco has been committed to sialic acid research for many years, and we use anti-sialyl antigen antibodies, such as anti-N-acetylneuraminic acids (Neu5Ac) antibodies, anti-N-glycolylneuraminic acids (Neu5Gc) antibodies, and anti-polysialic acid antibodiesto analyze cell surface sialic acid.

Functions of Sialic Acids

Sialic acids are an important molecule with high structural diversity present in mammals, lower vertebrates, certain bacteria, viruses, protozoa, and fungi. It is mainly located at the end of glycoproteins, glycolipids, capsular and tissue polysialic acids, and bacterial lipopolysaccharides. Due to their terminal position and electronegativity characteristics, sialic acids mediate cellular recognition, communication, aggregation, development, reproduction, signal transduction, and immunity. In addition, sialic acids also play important roles in tumor biology, such as promoting immune escape, tumor proliferation and metastasis, and tumor angiogenesis as well as resisting apoptosis and cancer therapy.

Fig.1 Biological and pathological roles of sialic acids. (Ghosh, 2020)

Sialic Acid-Specific Antibodies

Due to their highly selective and specific interactions, antibodies are used to study sialic acids, sialyl glycans, and sialic acids modification on the cell surfaces. Neu5Ac, Neu5Gc, gangliosides, O-acetylated sialic acids, sialyl Lewis a (SLe^a), and sialyl Lewis x (SLe^x) are recognized by specific antibodies. Anti-Neu5Ac antibodies recognize glycoproteins containing sialic acid residues. Monoclonal antibodies against Neu5Gc are highly specific for certain Neu5Gc-containing glycans, while polyclonal antibodies recognize specific types of sialic acids. An IgG antibody has been identified against O-acetylated sialic acid in the serum of patients with acute lymphoblastic leukemia (ALL). At present, many anti-polysialic acid antibodies have been developed, such as monoclonal antibody A2B5 and monoclonal antibody 5A5. Gangliosides are sialic acid-containing glycosphingolipids, and specific antibodies are used to detect different types of gangliosides on the cell surface. The first monoclonal antibody N 19-9 against SLe^a has been used to detect carbohydrate antigen 19-9 (CA 19-9) in the serum of patients with gastrointestinal cancer. The highly specific antibody CSLEX1 has been used to analyze the role of SLe^x during immunization and inflammation.

Fig.2 Double immunofluorescence analyses using the anti-sialic acid antibody. (Zhang, 2018)

Our Services

CD BioGlyco uses a range of antibodies to analyze sialic acids, sialyl glycans, and their modifications on the cell surface. Antibodies used include but are not limited to:

• Anti-Neu5Ac antibodies

Anti-Neu5Ac antibodies recognize Neu5Ac on the non-reducing terminal galactose (Gal) residues of glycoproteins and gangliosides.

• Anti-Neu5Gc antibodies

We have monoclonal and polyclonal anti-Neu5Gc antibodies to analyze the highly specific glycans on the cell surface.

• Anti-O-acetylated sialic acids antibodies

CD BioGlyco detects and analyzes O-acetylated sialic acids on the cell surface.

• Anti-polysialic acid antibodies

Anti-polysialic acid antibodies are used to detect and differentiate between different oligosaccharides/polysialic acids.

• Anti-gangliosides antibodies

Specific anti-ganglioside antibodies are used to analyze different types of gangliosides on the surface of tumor cells.

• Anti-SLe^a antibodies

We detect CA 19-9 in serum by anti-SLe^a antibodies.

• Anti-SLe^x antibodies

Anti-SLe^x antibodies are used to identify high levels of SLe^x expressed in cells.

CD BioGlyco has accumulated extensive experience in the analysis of sialic acids. Our perfect analytical strategies and experienced researchers provide full assurance for our clients' analytical results. If you are interested in our strategies, please feel free to contact us for more information.

References:

1. Ghosh, S. Sialic acid and biology of life: An introduction. Sialic acids and sialoglycoconjugates in the biology of life, health and disease. 2020.
2. Zhang, X.; et al. Recent approaches for directly profiling cell surface sialoform. Glycobiology. 2018, 28(12): 910-924.