IL2 and eye infection: CNS demyelination did not occur in macrophage-intact mice that were ocularly infected with WT HSV-1 in the absence of an external source of IL-2 [19,20,22–24] and CNS demyelination did not occur on depletion of T cells, B cells, dendritic cells (DCs), or natural killer (NK) cells following ocular infection with WT HSV-1 [22].