MX1 and viral infectious disease: We examined Ifit1 and Ifit2, which have been shown to respond to multiple viral infections in the brain [19,21]; Ifi202b, which has previously been shown to be upregulated by microglia following LACV and other viral infections in the brain [22]; and Mx1, which has been shown to restrict LACV growth in vitro and in transgenic mice, although the protein is non-functional in WT B6 mice [23,24].