Figure 3.

 Viral hepatitis sensitised for tumour necrosis factor related apoptosis inducing ligand (TRAIL) mediated apoptosis and steatosis. (A) Viral hepatitis was induced by intravenous application of 1×10¹⁰ pfu/g of AdlacZ into Balb/c mice. After 40 hours whole cell extracts of the livers were isolated and investigated for protein expression of TRAIL, DR5, DcR1, DcR2, and β-actin by western blot experiments. (B) Adenoviral vectors AdGFP, AdFasL, and Ad-TRAIL (1×10⁷ pfu/g) were administered into the tail vein of Balb/c mice 24 hours after pretreatment with 5×10⁷ pfu/g of AdlacZ. Twenty four hours after the last injection, apoptosis of hepatocytes was analysed by TUNEL assay (magnification 200×) and steatosis by fat red staining (magnification 200×). Figure shows representative data of four independent experiments. (C) Adenoviral vectors AdGFP, AdFasL, and AdTRAIL (1×10⁷ pfu/g) were administered into the tail vein of Balb/c mice 24 hours after pretreatment with 5×10⁷ pfu/g of AdlacZ. Twenty four hours after the last injection, livers were harvested for caspase 8 assays. FasL and TRAIL significantly (*) induced caspase 8 activity. C 8 inhi., caspase 8 inhibitor. (D) In animals with adenoviral hepatitis, one hour prior to AdTRAIL application, anti-TRAIL antibody N2B2 (250 μg / mouse) or isotype control antibody (250 μg/mouse) was injected into the tail vein. Hepatic steatosis was assessed by fat red staining. Administration of TRAIL neutralising antibody significantly (*) inhibited TRAIL mediated hepatic steatosis. Figure shows representative data of four independent experiments (magnification 600×).