In colon epithelia, Clostridium perfringens enterotoxin causes focal leaks by targeting claudins which are apically accessible due to tight junction derangement
Autor/innen
- M. Eichner
- C. Augustin
- A. Fromm
- A. Piontek
- W. Walther
- R. Buecker
- M. Fromm
- G. Krause
- J.D. Schulzke
- D. Guenzel
- J. Piontek
Journal
- Journal of Infectious Diseases
Quellenangabe
- J Infect Dis 217 (1): 147-157
Zusammenfassung
Clostridium perfringens enterotoxin (CPE) causes food poisoning and antibiotic-associated diarrhea. It uses some claudin tight junction proteins (e.g. claudin-4) as receptors to form Ca(2+)-permeable pores in the membrane damaging epithelial cells in small intestine and colon. We demonstrate that only a subpopulation of colonic enterocytes which are characterized by apical dislocation of claudins are CPE-susceptible. CPE-mediated damage was enhanced if paracellular barrier was impaired by Ca(2+)-depletion, proinflammatory cytokine TNF{alpha} or dedifferentiation. Microscopy, Ca(2+)-monitoring, and electrophysiological data showed that CPE-mediated cytotoxicity and barrier disruption was limited by extent of CPE-binding. The latter was restricted by accessibility of non-junctional claudin molecules such as claudin-4 at apical membranes. Focal-leaks detected in HT-29/B6 colonic monolayers were verified for native tissue using colon biopsies. These mechanistic findings indicate how CPE-mediated effects may turn from self-limiting diarrhea into severe clinical manifestation such as colonic necrosis - if intestinal barrier dysfunction e.g. during inflammation facilitates claudin accessibility.