They are observed in peripheral blood, secondary lymphoid organs, and various tissues. DNT cells are expanded in patients with autoimmune lymphoproliferative syndrome, inflammatory autoimmune conditions (systemic lupus erythematosus, Sjögren's syndrome, psoriasis) where DNT cells infiltrate target organs and produce pro-inflammatory cytokines (IL-17, IFN-γ) [27-29]. The gene discussed is IL17A; the disease is psoriasis.