Biologic activity of cell-associated staphylococcal enterotoxin A.

Cell associated staphylococcal enterotoxin A, released by lysostaphin treatment of Staphylococcus aureus cells, was found to be biologically active in cynomolgus monkeys. The activity was comparable to that of extracellular enterotoxin A; six of six monkeys vomited within 5 h in response to extracellular enterotoxin and four of six also vomited in response to the same serologic level (4.8 micrograms per monkey) of cell-associated enterotoxin. Feeding S. aureus cells containing cell-associated enterotoxin A to cynomolgus monkeys resulted in emesis in three of five monkeys within 3 h. This suggests that consumption of S. aureus cells could lead to staphylococcal intoxication.