STAT1 and viral infectious disease: In response to viral infection, activated immune cells, such as mononuclear cell, Iba-1 expressing microglia, and/or macrophages, were shown to infiltrate from the periphery and to produce inflammatory cytokines: tumor necrosis factor (TNF)-α, interferon (IFN)-β, signal transducer and activator of transcription 1 (STAT1), and an IFN-induced protein with tetratricopeptide repeats 1 (IFIT1) to exacerbate inflammation in the cerebella [90].