Increased Susceptibility to Staphylococcal Enterotoxin B Intoxication in Mice Primed with Actinomycin D
WALTER REED ARMY INST OF RESEARCH WASHINGTON DC DIV OF PATHOLOGY
Pagination or Media Count:
Mice BALBcJ, C3HHeN, and C3HHeJ primed with actinomycin D became highly susceptible to lethal intoxication with staphylococcal enterotoxin B SEB. The mice underwent toxicosis and toxic shock and died. Actinomycin D- primed C3HHeN and C3HHeJ mice showed equal sensitivity to SEB, suggesting that bacterial lipopolysaccharide derived from gram-negative bacteria in the gut may not be an important cofactor in intoxication. In a time course study of the illness, prominent pathological changes characterized by blood congestion and thickening of alveolar septa were seen in the lung, while blood congestion, inflammation, epithelial cell flattening, and villous blunting were seen in the small intestine. In lymphoid tissues, such as the spleen, congestion, inflammation, and lymphoid cell depletion were the major reactions. The pathological features of the mice had many similarities to those of rhesus monkeys intoxicated with intravenous SEB. The actinomycin D-primed C3HHeJ mice are thus an ideal mouse model for studying SEB toxicosis and toxic shock.