Interaction of staphylococcal enterotoxin B with cell cultures of human embryonic intestine

Schaeffer, W. I. (Massachusetts Institute of Technology, Cambridge), J. Gabliks, and R. Calitis. Interaction of staphylococcal enterotoxin B with cell cultures of human embryonic intestine. J. Bacteriol. 91:21-26. 1966.-The cytotoxic effect of staphylococcal enterotoxin B upon human embryonic intestine cell cultures is characterized by retraction of cells from the monolayer. This is followed by clumping of the retracted cells to form clear areas in the monolayer and finally by sloughing of the clumps from the glass surface. The 50% effective dose of the toxin, determined by protein analysis of the cultures used in titration studies, was found to be between 40 and 60 mug/ml. The cytotoxic property of the enterotoxin was completely neutralized by 3.9 x 10(-5) ml of specific antitoxin per mug of toxin. The cytotoxicity was found to be slightly enhanced by 2.2 g of bicarbonate per liter of Eagle's basal medium (Earle's salt solution level), the absence of serum, the absence of penicillin and streptomycin, and the presence of 2.8 mmoles of calcium in the medium. The cytotoxicity was profoundly influenced by the age of the culture. No cytotoxicity was evident until after 2 days of growth had taken place, when the cell number was approximately 4.0 x 10(5) cells per culture.