The “immune-deficient” A/Jcr mice infected with the IFN-γ-expressing C. neoformans H99 not only recovered from the primary infection, but were also completely protected against a second challenge with a pathogenic C. neoformans strain, as a result of the protection mediated by IFN-γ-producing CD4+ Th1 cells [27]. Here, IFNG is linked to infection.