Clostridium perfringens epsilon-toxin acts on MDCK cells by forming a large membrane complex

Epsilon-toxin is produced by Clostridium perfringens types B and D and is responsible for a rapidly fatal enterotoxemia in animals, which is characterized by edema in several organs due to an increase in blood vessel permeability, The Madin-Darby canine kidney (MDCK) cell line has been found to be susceptible to epsilon-toxin (D, W, Payne, E, D, Williamson, H. Havard, N, Modi, and J, Brown, FEMS Microbiol. Lett. 116:161-168, 1994), Here we present evidence that epsilon-toxin cytotoxic activity is correlated with the formation of a large membrane complex (about 155 kDa) and efflux of intracellular K+ without entry of the toxin into the cytosol, Epsilon-toxin induced swelling, blebbing, and lysis of MDCK cells, Iodolabeled epsilon-toxin bound specifically to MDCK cell membranes at 4 and 37 degrees C and was associated with a large complex (about 155 kDa), The binding of epsilon-toxin to the cell surface was corroborated by immunofluorescence staining, The complex formed at 37 degrees C was more stable than that formed at 4 degrees C, since it was not dissociated by 5% sodium dodecyl sulfate and boiling.