Increased toxicity of endotoxin for tumor-bearing mice and mice responding to bacterial pathogens: macrophage activation as a common denominator.

Mice bearing the syngeneic SA-1 sarcoma or treated with live Mycobacterium bovis BCG or Formalin-killed Corynebacterium parvum acquired a greatly increased susceptibility to the lethal effects of endotoxin. In all three experimental models, the acquisition of increased sensitivity to endotoxin was concordant with the generation of a systemically activated macrophage system.