Recently, Lee et al. showed that T‐cell‐specific deletion of EP2 and EP4 receptors in combination suppressed psoriasis‐like skin inflammation induced by subcutaneous injection of IL‐23 or imiquimod with concomitant suppression of IL‐17+ and IL‐17+IFN‐γ+ T‐cell accumulation in the lesion, suggesting the critical role of T‐cell‐intrinsic EP2/EP4 receptor signalling in the development of immune inflammation (Lee et al., 2018). Here, IL17A is linked to psoriasis.