ISG15 and infection: During E30 infection, genes associated with the type I IFN signaling pathway (Isg15, Mx1, Mx2, Sp100, Ifit1, Ifit3, Ifih1, Irf7, Irf9, guanylate-binding proteins 2 [Gbp2], and Stat1) and defense response to viruses (Ddx58, Ddx60, Zbp1, Oas2, Nlrc5, and Eif2ak2) were significantly upregulated.