Increased cyclic adenosine 3',5'-monophosphate content in guinea pig ileum after exposure to Staphylococcus aureus delta-toxin.

To compare Staphylococcus aureus delta-toxin with cholera toxin, which is known to increase cellular cyclic adenosine 3',5'-monophosphate (cAMP), studies were undertaken to determine the effect of delta-toxin on the cAMP content of guinea pig ileum maintained in vitro. Concentrations of delta-toxin as low as 0.40 mug/ml increased cAMP levels in guinea pig ileum after 2 h of incubation. Histological damage was seen in ileum exposed for 2 h to delta-toxin concentrations of 100 mug/ml. As little as 3 mug of delta-toxin increased vascular permeability in guinea pig skin. Permeability changes became evident within 5 min and were maximal within 6 h, whereas those produced by cholera toxin required 24 h to become maximal. Benadryl did not interfere with the ability of these toxins to alter vascular permeability. Purified egg lecithin reduced the effectiveness of delta-toxin in the skin but did not inhibit cholera toxin. Delta-toxin in concentrations as low as 0.1 mug/ml caused dislodgement of HeLa cells in tissue cultures. Therefore, delta-toxin appears unique in being the only bacterial toxin, currently known to alter water absorption in the ileum, that is capable of both increasing cAMP levels and being cytotoxic. These findings suggest a possible role for delta-toxin in the pathogenesis of staphylococcal enteritis.