ISG15 and infection: In the brain (Fig. 2a and Supplementary Fig. 2a), infection with Bov342 induced the expression of type-I (Ifna5, Ifnb), -II (Ifng), and -III (Ifnl2) interferons (IFN), interferon stimulated genes (ISGs) (Isg15, Ifit1, Mx1, Oas1), and pro-inflammatory cytokines (Il1b, Il6, and Tnfa) at endpoint.