CD4 and fungal infectious disease: Despite the need for CD4+ T-cell help for CD8+ T-cell activation and memory maintenance in viral and bacterial infection scenarios, using mouse models of fungal infections against Pneumocystis, Histoplasma, and Blastomyces, the studies have shown that antifungal CD8+ T cells can be induced, retained as long-lasting memory, and recalled upon the challenge to provide immunity independent of the T-cell help during mouse models of Pneumocystis, Histoplasma, and Blastomyces infections (8, 13–16).