IL6 and graft versus host disease: Liver: IL-6 together with other cytokines is important for liver regeneration; the prolonged effect of trans-stimulation seems more important than classical signaling (96, 97). Clinical IL-6 inhibition can cause increased liver transaminases (98), but it is not known whether IL-6 targeting, potentially liver-toxic drugs and concomitant immune-mediated injury due to GVHD, will increase the risk of severe liver toxicity in allotransplant recipients.