Interferon (IFN) Regulatory Factor 8 and IFN-γ: a complex nexus in Japanese Encephalitis virus infection.

Microglial cells, the resident macrophages in the brain, play a vital role in Japanese encephalitis virus (JEV) pathogenesis. The deregulated activity of microglia can be lethal for the brain. Interferon regulatory factor 8 (IRF8) is a myeloid lineage transcription factor involved in microglial activation. However, the impact of IRF8 modulation on JEV replication remains elusive. We summarize that in the murine model of JEV encephalitis, the death due to JEV appears to be primarily virus-mediated rather than immune-mediated in the Irf8-/- and Ifn-/- mice. Our study also provides evidence for the possible association between IRF8 and IFNγ that drives immune cell infiltration and modulate viral replication in the brain. Further, our RNA-Seq data of the WT and Ifn-/- mice provide a piece of valuable gene information that is regulated with IRF8.

Lack of Interferon (IFN) Regulatory Factor 8 Associated with Restricted IFN-γ Response Augmented Japanese Encephalitis Virus Replication in the Mouse Brain. J Virol. 2021 Oct 13;95(21):e0040621. DOI: 10.1128/JVI.00406-21. Epub 2021 Aug 11. PMID: 34379515;