Moreover, Lima et al. performed IHC staining and Western blot experiments to investigate the localization and expression of IL-17 in HS skin and detected a number of IL-17+ cells that were significantly increased in lesional and perilesional skin, compared to healthy controls; interestingly, neutrophils were identified as a major source of IL-17 in HS skin [30]. The gene discussed is IL17A; the disease is histiocytic sarcoma.