This dual role of IL-17 in murine data may have much relevance to human disease as treatment with secukinumab, a human anti-IL-17A monoclonal antibody, had no beneficial effect in patients with moderate-to-severe CD and was associated with higher frequencies of fungal infections which did not occur in larger trials of psoriasis and rheumatoid arthritis [173]. The gene discussed is IL17A; the disease is psoriasis.