Moran and colleagues have showed the effects of anti-TNF-α therapy in skin-infiltrating T cells: a significant reduction of Th17 cells’ frequency was seen in both the lesional and perilesional skin of HS patients treated with anti-TNF-α compared with anti-TNF-α-naïve patients, and the Th17:Treg cell ratio (this ratio was significantly increased in HS lesional skin compared with healthy control samples) was normalized [124]. This evidence concerns the gene TNF and histiocytic sarcoma.