Unidentified non-galactose cell-surface glycan receptor

The unidentified non-galactose cell-surface glycan receptor is a hypothesized carbohydrate structure on the surface of human intestinal epithelial cells that serves as the primary binding site for Clostridioides difficile toxin A (TcdA). While TcdA is known to bind the alpha-galactose (Gal-alpha-1,3-Gal-beta-1,4-GlcNAc) epitope in many animal species, humans lack this specific glycan, leading researchers to conclude that the toxin utilizes an alternative, as-yet unidentified non-galactose-containing glycan for host cell entry. This receptor facilitates the attachment and subsequent endocytosis of TcdA, which then disrupts the host cell cytoskeleton via Rho GTPase glucosylation, causing the symptoms of C. difficile infection. Therapeutic strategies, such as the monoclonal antibody actoxumab, aim to neutralize the toxin before it can interact with these cell-surface receptors. Understanding the precise molecular identity of this glycan remains a significant area of research in the development of anti-toxin therapies and diagnostics for antibiotic-associated diarrhea.

Other names

Human TcdA receptorNon-alpha-galactose TcdA receptorClostridioides difficile toxin A human receptor