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Published on: August 19, 2016
Clostridium perfringens epsilon toxin rapidly decreases membrane barrier permeability of polarized MDCK cells
Laetitia Petit1, Maryse Gibert, Abdelkader Gourch
1Unité des Bactéries Anaérobies et Toxines, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris Cedex 15, France.
Abstract:
Epsilon toxin is produced by Clostridium perfringens types B and D which are responsible for fatal intestinal diseases in animals. The main biological activity of epsilon toxin is the production of oedema in various organs. We have previously found that epsilon toxin forms a large membrane complex in MDCK cells which is not internalized into cell, and induces cell volume enlargement and loss of cell viability (Petit, L., Gibert, M., Gillet, D., Laurent-Winter, C., Boquet, P., Popoff, M. R. (1997) J Bacteriol 179, 6480-6487). Here, we show that epsilon toxin is very potent to decrease the trans-epithelial electrical resistance of polarized MDCK cells grown on filters without altering the organization of the junctional complexes. The dose-dependent decrease in trans-epithelial electrical resistance, more marked when the toxin was applied to the apical side than to the basal side of MDCK cells, was associated with a moderate increase of the paracellular permeability to low-molecular-weight compounds but not to macromolecules. Epsilon toxin probably acts by forming large membrane pores which permit the flux of ions and other molecules such as the entry of propidium iodide and finally to the loss of cell viability.
Insights
Clostridium perfringens epsilon toxin damages animal intestines by forming membrane pores. This toxin decreases trans-epithelial electrical resistance in cells, leading to cell death.
Area of Science:
- Microbiology
- Cell Biology
- Toxicology
Background:
- Epsilon toxin, produced by Clostridium perfringens types B and D, causes fatal intestinal diseases in animals.
- The toxin's primary activity involves inducing edema in various organs.
- Previous research indicated epsilon toxin forms non-internalized membrane complexes in MDCK cells, causing cell enlargement and death.
Purpose of the Study:
- To investigate the effect of epsilon toxin on the integrity of polarized epithelial cell layers.
- To determine how epsilon toxin impacts trans-epithelial electrical resistance and paracellular permeability.
- To elucidate the mechanism by which epsilon toxin affects cell viability.
Main Methods:
- Utilized polarized Madin-Darby canine kidney (MDCK) cells grown on filters.
- Measured trans-epithelial electrical resistance (TEER) after apical and basal application of epsilon toxin.
- Assessed paracellular permeability to low- and high-molecular-weight compounds.
- Observed effects on junctional complex organization.
Main Results:
- Epsilon toxin significantly decreased TEER in a dose-dependent manner.
- The reduction in TEER was more pronounced when the toxin was applied apically compared to basally.
- Paracellular permeability to small molecules increased moderately, while permeability to macromolecules remained unchanged.
- Epsilon toxin likely forms large membrane pores, facilitating ion and molecule flux, leading to cell death.
Conclusions:
- Epsilon toxin disrupts the barrier function of polarized epithelial cells by reducing TEER.
- The toxin's pore-forming activity affects ion and small molecule transport across the cell layer.
- These disruptions contribute to the observed loss of cell viability.
