The haemagglutinin of Clostridium botulinum type C progenitor toxin plays an essential role in binding of toxin to the epithelial cells of guinea pig small intestine, leading to the efficient absorption of the toxin

Microbiology (Reading). 1997 Dec:143 ( Pt 12):3841-3847. doi: 10.1099/00221287-143-12-3841.


Binding of the purified type C 7S (neurotoxin), 12S and 16S botulinum toxins to epithelial cells of ligated small intestine or colon of the guinea pig (in vivo test) and to pre-fixed gastrointestinal tissue sections (in vitro test) was analysed. The 16S toxin bound intensely to the microvilli of epithelial cells of the small intestine in both in vivo and in vitro tests, but did not bind to cells of the stomach or colon. The neurotoxin and 12S toxin did not bind to epithelial cells of the small intestine or to cells of the stomach or colon. Absorption of the toxins was assessed by determining the toxin titre in the sera of guinea pigs 6-8 h after the intra-intestinal administration of the toxins. When the 16S toxin [1 x 10(5) minimum lethal dose (MLD)] was injected, 200-660 MLD ml-1 was detected in the sera, whereas when the 12S toxin (2 x 10(5) MLD) or 7S toxin (2 x 10(5) MLD) was injected, little toxin activity was detected in the sera. Therefore, the haemagglutinin of type C 16S toxin is apparently very important in the binding and absorption of botulinum toxin in the small intestine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites
  • Bodily Secretions
  • Botulinum Toxins / chemistry
  • Botulinum Toxins / pharmacokinetics*
  • Botulinum Toxins / toxicity*
  • Clostridium botulinum / pathogenicity
  • Clostridium botulinum / physiology*
  • Colon
  • Drug Stability
  • Gastric Mucosa / microbiology
  • Guinea Pigs
  • Intestinal Absorption
  • Intestinal Mucosa / microbiology*
  • Intestinal Mucosa / physiology
  • Intestine, Small
  • Microscopy, Immunoelectron
  • Microvilli / microbiology*
  • Microvilli / physiology
  • Microvilli / ultrastructure
  • Organ Specificity
  • Protein Precursors / pharmacokinetics
  • Protein Precursors / toxicity


  • Protein Precursors
  • Botulinum Toxins
  • botulinum toxin type C