Human respiratory epithelial cell sialylated glycoconjugates (SAs)

Human respiratory epithelial cell sialylated glycoconjugates are complex carbohydrates (glycans) terminated with sialic acid residues, primarily N-acetylneuraminic acid (Neu5Ac), attached to glycoproteins and glycolipids on the surface of respiratory cells (Nicholls et al., 2007). These molecules serve as critical host cell receptors for various pathogens, most notably influenza viruses, where the viral hemagglutinin (HA) protein binds to specific sialic acid linkages—α2,6-linkages are predominant in the human upper respiratory tract, while α2,3-linkages are more common in the lower respiratory tract (Shinya et al., 2006). Beyond their role in viral entry, these glycoconjugates are involved in essential biological processes such as cell-cell recognition, signal transduction, and the maintenance of the mucosal barrier (Varki, 2008). In the context of disease, they are the primary targets for viral attachment in influenza and other respiratory infections, and their expression patterns can influence host susceptibility and disease severity. Therapeutic strategies targeting these glycoconjugates include the use of host-directed sialidases like DAS181, which enzymatically remove the sialic acid residues to prevent viral infection, as well as neuraminidase inhibitors that prevent the release of new viral particles by blocking the cleavage of these same glycoconjugates (Malakhov et al., 2006).

Other names

Sialic acid-containing glycoconjugatesSialylated glycansInfluenza virus receptorsα2,3-linked sialic acidsα2,6-linked sialic acidsNeu5Ac-containing glycoconjugatesRespiratory sialyl-glycansSialic acid receptors

Enzymatic removal of terminal sialic acid residues from the host cell surface to prevent viral attachment and entry (e.g., DAS181), or inhibition of viral neuraminidase to prevent the cleavage of these residues during viral egress (e.g., Oseltamivir).