Tetanus toxin heavy-chain C fragment (TTC)

The Tetanus toxin heavy-chain C fragment (TTC) is the 50 kDa C-terminal domain of the tetanus neurotoxin (TeNT) produced by Clostridium tetani (UniProt P04958). It serves as the binding domain, mediating the toxin's attachment to polysialogangliosides like GT1b and GD1b on neuronal membranes (PubMed: 15504414). Once bound, TTC facilitates the internalization and retrograde axonal transport of the toxin from the neuromuscular junction to the central nervous system (PubMed: 11597379). Because it lacks the light chain's zinc-endopeptidase activity, TTC is non-toxic but highly immunogenic, making it a critical component in tetanus toxoid vaccines (StatPearls: NBK459210). Therapeutic interventions, such as Tetanus Immune Globulin, work by providing neutralizing antibodies that bind to this fragment and prevent neuronal entry (NIH: PubChem CID 16132345). Beyond its role in disease, TTC is utilized in research as a carrier for delivering drugs or genes to the nervous system due to its specific neurotropism (PubMed: 22403574).

Other names

Fragment CTeNT-HcTetCTetanus toxin C-fragmentHc domain

Neutralization of the toxin by providing antibodies that bind to the C-fragment, thereby preventing its attachment to neuronal gangliosides and subsequent internalization into the central nervous system (StatPearls: NBK459210).