Bacillus anthracis edema toxin inhibits Staphylococcus aureus enterotoxin B effects in vitro: a potential protein therapeutic?

Various in vitro effects of staphylococcal enterotoxin B (SEB) on human peripheral blood mononuclear cells were mitigated by Bacillus anthracis edema toxin. In particular, levels of some SEB-induced cytokines (tumor necrosis factor alpha, gamma interferon) and chemokines (monocyte chemoattractant protein 1, macrophage inflammatory protein 1 alpha [MIP-1alpha], MIP-1beta) were significantly diminished or even nonexistent, depending upon the timing of edema toxin administration. Overall, these results suggest a novel use of B. anthracis edema toxin against a bacterial superantigen.