%0 Journal Article %A Zimmermann, Albert %A Hauka, Sebastian %A Maywald, Marco %A Le, Vu Thuy Khanh %A Schmidt, Silvia K. %A Däubener, Walter %A Hengel, Hartmut %T Checks and balances between human cytomegalovirus replication and indoleamine-2,3-dioxygenase %D 2014 %J Journal of General Virology, %V 95 %N 3 %P 659-670 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.061994-0 %I Microbiology Society, %X Despite a rigorous blockade of interferon-γ (IFN-γ) signalling in infected fibroblasts as a mechanism of immune evasion by human cytomegalovirus (HCMV), IFN-γ induced indoleamine-2,3-dioxygenase (IDO) has been proposed to represent the major antiviral restriction factor limiting HCMV replication in epithelial cells. Here we show that HCMV efficiently blocks transcription of IFN-γ-induced IDO mRNA both in infected fibroblasts and epithelial cells even in the presence of a preexisting IFN-induced antiviral state. This interference results in severe suppression of IDO bioactivity in HCMV-infected cells and restoration of vigorous HCMV replication. Depletion of IDO expression nonetheless substantially alleviated the antiviral impact of IFN-γ treatment in both cell types. These findings highlight the effectiveness of this IFN-γ induced effector gene in restricting HCMV productivity, but also the impact of viral counter-measures. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.061994-0