Biological activities of toxins A and B of Clostridium difficile

Examination of the biological activities of the two known toxins of Clostridium difficile revealed that one of the toxins (toxin A) elicited a hemorrhagic fluid response in rabbit intestinal loops and a positive fluid response in infant mice. The other toxin (toxin B) did not produce a significant fluid response in either model, although the toxin was more lethal in infant mice. Both toxins elicited erythematous and hemorrhagic skin reactions and increased vascular permeability in rabbit skin.