Although interferon-γ (INF-γ)-secreting CD8+ T cells, promoted by CD4+ T cells, mast cells and dendritic cells, have a central role in the etiopathogenesis of alopecia areata (19), recent research has also pointed out the role of Th2 response, also explaining the association between alopecia areata and atopic dermatitis. This evidence concerns the gene CD4 and atopic eczema.