Group 3 innate lymphoid cells lack rearranged antigen-specific receptors, rely on the transcription factor RORγt, and respond to IL-1β and IL-23; a subset of group 3 innate lymphoid cells is associated with production of IL-17A and IL-22 in psoriasis lesions (Villanova et al, 2014). Here, IL17A is linked to psoriasis.