Histo-blood group antigen carbohydrate ligands on intestinal epithelial cells

Histo-blood group antigens are complex fucosylated carbohydrate structures that occur as terminal residues on glycoproteins and glycolipids on red blood cells, mucosal epithelial cells (including intestinal epithelial cells), and as free antigens in secretions such as saliva and milk. On intestinal epithelial cells they form part of the glycocalyx and include ABH (A, B, H) and Lewis (e.g., Lewis a, Lewis b) antigens, whose synthesis depends on the activity of glycosyltransferases encoded by the ABO, FUT2 (secretor), and FUT3 (Lewis) genes. These carbohydrate ligands modulate host–microbe interactions and have been proposed to act as receptors or coreceptors for several human enteric viruses, notably human noroviruses and some human rotaviruses, by binding viral capsid or spike proteins on the apical surface of intestinal epithelial cells, thereby influencing susceptibility to viral gastroenteritis. They also serve as attachment sites for certain bacteria (for example, *Helicobacter pylori* in the stomach) and more broadly affect susceptibility to infection and aspects of mucosal immunity, but they are not single, discrete protein receptors and are not typically considered conventional drug targets.

Other names

Histo-blood group antigensHisto-blood group carbohydrate antigensABH and Lewis histo-blood group antigensHisto-blood group antigen ligands on intestinal epitheliumHisto-blood group antigen carbohydrates on mucosal epithelial cells