IL-15 has been implicated in the pathogenesis of AA: in the C3H/HeJ inbred mouse model of AA, disease development was prevented with an anti–IL-15 receptor antibody (36); IL-15 is elevated in the serum of patients with AA (81–84), and increased expression of IL-15 and the IL-15 receptor (IL-15Rα) in NKG2D+CD8+ T cells and around lesional scalp HFs has also been identified at the mRNA level (36, 85). This evidence concerns the gene IL15 and Hand-foot syndrome.