IL17A and depressive disorder: To further clarify the critical role of IL‐17A in triggering depression in psoriatic disease, intracerebroventricular injection of anti‐IL‐17A antibody was implemented during the period of IMQ application for the establishment of psoriasiform dermatitis, which is a technologically matured administration way in animal experiments of psychiatric and psychological disorders, and also commonly used in the screen research of antidepressant drugs and mechanism exploration [44, 45, 46, 47].