FIG. 5.

The antiviral effect of IL-18 is mediated by IFN-γ and IFN-α/β. (Top Panel) Age- and serum HBeAg-matched male transgenic mice (lineage 1.3.32) were intraperitoneally injected with 250 μg of hamster MAbs to IFN-γ or TNF-α and sacrificed 24 h after administration of a single dose (10 μg) of IL-18. Control mice were simultaneously injected with 250 μg of irrelevant hamster IgG and sacrificed at the same time after IL-18 administration. Results were compared with those observed in livers from 2 age-, sex-, and serum HBeAg-matched transgenic littermates injected with saline (NaCl). Total hepatic DNA was analyzed for HBV DNA by Southern blot analysis as indicated. The sALT activity values at the time of autopsy are indicated for each mouse and expressed in units/liter. (Bottom panel) Age- and serum HBeAg-matched male transgenic mice (lineage 1.3.46) that were either heterozygous (+/−) or homozygous (−/−) for the IFN-α/β receptor null mutation were injected with 10 μg of IL-18, sacrificed 24 h later and their livers were processed as described above.