Histo-blood group antigen receptor (HBGA receptor)

Histo-blood group antigens are structurally diverse glycan epitopes present on glycoproteins and glycolipids of many cell types, particularly epithelial tissues of the gut. They include the ABO, Lewis, and secretor families of antigens, defined by their constituent sugars and carbohydrate linkages and are synthesized by specific glycosyltransferases[1][3][6]. Certain viral pathogens, especially human norovirus and rotavirus, exploit these antigens as attachment factors (functionally acting as "receptors") to mediate entry into host cells. The recognition profiles are highly strain-specific, and the presence/absence of certain HBGAs influences susceptibility to infection. This role has made HBGAs important in understanding infectious disease epidemiology, host–pathogen interaction, and the development of antiviral strategies[1][2][4][5][6][7]. Key limitations: - HBGAs are not conventional molecular targets such as proteins, channels, or enzymes. - The term "receptor" in this context is functional (virus-ligand specific), not necessarily descriptive of a protein-based molecular receptor[5][6]. - HBGAs encompass several carbohydrate structures (e.g., A-type, B-type, H, Lewis b, Lewis x antigens), not a single entity, increasing target complexity and polymorphism[1][3][6]. For more precise molecular targeting or drug development, consider focusing on specific virus–HBGA interactions or the enzymes that biosynthesize these epitopes (e.g., fucosyltransferases such as FUT2, FUT3)[1][3][6].

Other names

Histo-blood group antigens (HBGAs)blood group antigensABH antigensLewis antigenssecretor antigens

Inhibition of viral attachment to HBGAs by small molecules or antibodies blocks infection initiation