CH25H and infection: Following infection with HSV-1, TLR2 and TLR4 are induced to activate simultaneously, and in turn, TLR2 forms a dimer with TLR1, or TLR6, which then induces IFN-β in neurons and IFN-α in astrocytes, and these IFNs subsequently induce the expression of ISGs such as viperin, CH25H (cholesterol-25-hydroxylase), oligoadenylate synthase2 (OAS2), latent RNase (RNase L), PKR, and IFIT1 (59, 60).