Muramyl peptides confer hepatoprotection against murine viral hepatitis

The hepatoprotection induced by synthetic muramyl peptides was investigated using a model of lethal murine mouse hepatitis MHV-3 virus infection. MDP and a nonpyrogenic analog, Murametide, inhibited the steep elevation of serum transaminases induced by MHV-3 irrespective of whether the immunomodulators were administered before or after the infection. A significant proportion of MDP or Murametide-treated animals, in contrast to controls, survived the MHV-3 infection. The histopathological examination of the liver revealed marked necrosis of the hepatic parenchymal cells and infiltration of the inflammatory cells in controls but not in MDP-treated animals.