Analytical and Functional Aspects of Antibody Sialylation

This review focuses on the role of antibody sialylation and methods for its quantitation. The recent attribution of the anti-inflammatory activity of IgG to the sialylation of its glycans in the Fc region has raised interest in the fine structure and analysis of the glycans. The anti-inflammatory fraction of intravenous IgG could be isolated with the Sambucus nigra lectin. Experimental strategies for the assessment of antibody sialylation are discussed. Thorough analysis of the lectin-binding fraction revealed that the antibody Fc region only binds to S. nigra lectin when two sialic acids are present, whereas for other glycoprotein ligands, one sialic acid appears sufficient.