IL17A and psoriasis: Skin inflammation–Human/patient data: IL-17A is increased in several skin disorders, including psoriasis, atopic dermatitis as well as neutrophilic, granulomatous, and bullous skin diseases (30)–Animal models: IL-17A contributes to skin inflammation in multiple models of cutaneous inflammation, including IMQ application and K5hTGFβ1 transgenic mice (17).