Fig. 5.

Type I IFN inhibits JHMV replication in differentiated glial cultures. (A) Type I IFN was measured in supernatants from cell cultures infected with JHMV and/or treated with IFN-γ (100 U/ml) at 24 and 48 h p.i. No detectable IFN-α/β was present in cultures infected with virus alone yet IFN-γ treatment resulted in IFN-α/β production at 24 h that increased by 48 h post-treatment. IFN-γ treatment of JHMV-infected cultures resulted in increased IFN-α/β production compared to IFN-γ treatment alone at both 24 and 48 h time points. (B) Treatment of JHMV-infected cultures with either 100 U/ml of recombinant IFN-α or IFN-β diminished viral replication compared to untreated cultures with a greater anti-viral effect observed with IFN-β (value below limit of detection, < 150 pfu/ml) compared to IFN-α (⁎p < 0.05). (C) Glial cultures were derived from progenitor cells obtained from type I IFNR−/− mice, infected with virus and treated with IFN-γ (100 U/ml) and viral titers determined at 48 h p.i. IFN-γ treatment resulted in a reduction (⁎p < 0.05) in viral titers when compared to media control cultures at either time point. Data are presented as average ± SEM and are representative of two independent experiments.