Human airway sialic acid receptor (alpha2,6-SA)

Human airway sialic acid receptors are terminal carbohydrate structures, predominantly alpha2,6-linked sialic acids, found on the surface of epithelial cells in the human respiratory tract. These receptors serve as the critical attachment point for the hemagglutinin protein of influenza viruses, facilitating viral entry into host cells (Shinya et al., 2006). The specific linkage of the sialic acid to the underlying galactose residue determines host specificity; human-adapted influenza viruses preferentially bind to alpha2,6-linkages found in the upper airway, while avian-adapted strains favor alpha2,3-linkages (Nicholls et al., 2007). Beyond influenza, these receptors are involved in the attachment of other respiratory pathogens, including parainfluenza viruses and certain bacteria. Therapeutic interventions targeting these receptors include the development of sialidases, such as DAS181, which enzymatically remove the sialic acid residues to prevent viral infection (Triana-Baltzer et al., 2009). Additionally, the interaction between these receptors and viral neuraminidase is the target of widely used antiviral drugs like oseltamivir, which prevent the release of new virions from the cell surface. Understanding the distribution and molecular configuration of these receptors is essential for assessing the pandemic potential of emerging zoonotic viruses (Moss et al., 2012).

Other names

alpha2,6-linked sialic acidNeu5Ac-alpha2,6-GalHuman-type influenza receptorSialic acid-containing glycoconjugateHost cell sialic acid

Enzymatic removal of terminal sialic acid residues from the host cell surface via sialidase activity to prevent viral attachment, or inhibition of viral neuraminidase to prevent the release of progeny virions from these receptors.