CIITA and infection: Corresponding to the above results that IFN-γ was elevated at higher levels in the HEP-Flury infected mouse brains, the IFN-γ-induced MHC class II transactivator gene (CIITA), MHC class II associated invariant chain (Ii; CD74) and MHC class II were all elevated more significantly following the HEP-Flury infection at 10 dpi than the CVS-11 infection (Figure 6).