IFNG and central nervous system infectious disorder: Instead, protection against disease and nervous system infection seen after challenge of mice immunized with ICP8−vhs− HSV-1 or ICP8− HSV-2 strains encoding B7 costimulation molecules correlates with the increased numbers of IFNγ-producing T cells these B7-expressing viruses elicit (Figures 6 through , 8 and [25]).