Susceptibility of various animals and cultured cells to exfoliative toxin produced by Staphylococcus hyicus subsp. hyicus.

In piglets inoculated with partially purified exfoliative toxin (pp-shET) produced by Staphylococcus hyicus subsp. hyicus, exfoliation was observed at 12 h after injection. Chickens inoculated with the same dose of pp-shET also showed exfoliation within 30 min of injection. However, exfoliation was not demonstrated in mouse, rat, guinea pig, hamster, dog or cat inoculated with pp-shET until 24 h after injection. In cultured cell lines, especially L-929 and Hep-2, the rounding effect occurred after incubation with pp-shET for 1 h. The rounding effect was also seen in five other cultured cells (NCTC 2544, HeLa/S3, HmLu-1, CHO and BHK-21) 6-24 h after exposure to pp-shET. These round cells survived for 72 h after inoculation and formed a monolayer 24 h after changeover to a toxin-free medium. The rounding effect was observed in cells after the formation of the monolayer, but not before. It was suggested that the rounding effect was not caused by the increase in cyclic AMP in cells inoculated with pp-shET but by the cleavage of intracellular contacts.