Detection of Sialic Acids on the Cell Surface Using Flow Cytometry

Abstract

We described a method to detect α2-3 linked and α2-6 linked sialic acids on the cell surface with using flow cytometry. Cells were fixed with 4% paraformaldehyde, and then α2-3 and α2-6 sialic acids were stained with biotinylated MAACKIA AMURENSIS LECTIN II (MALII) and biotinylated ELDERBERRY BARK LECTIN (SNA), respectively. Sialic acids on the cell surface were cleaved by sialidase in acetate buffer at pH 5.5 to confirm the specificity of staining. Streptavidin conjugated with Alexa flour 488 was used to detect biotinylated lectins. Thus, the α2-3 linked and α2-6 linked sialic acids on the cell surface were semi-quantitatively detected by flow cytometry.