TGFB1 and Hepatic fibrosis: As TGF-β is likely to be crucial to maintain the immune tolerance state and T-reg generation/function essential to the parasite, E. multilocularis could be responsible for the paradoxical decrease of Smad7 in the periparasitic granuloma and nearby liver; this might be one of the mechanisms for the early induction of immune tolerance and for the progression from chronic hepatic injury to hepatic fibrosis during E. multilocularis infection.