IL17A and psoriasis: Several researches have proved that consecutive 7-day application of 62.5 mg/mice/day IMQ cream on back skin induces significant psoriasis-like pathological change in C57BL/6 mice [18, 22, 24], we confirmed in our laboratory this modelling condition indeed induced classical pathological changes including the formation of white scales, thicken-induced skin wrinkle, as well as distinct redness on day 5 (Fig. 1a); However, blocking IL-17A pathway with anti-IL-17A antibody (10 mg/kg, 3 times/week) didn’t affect the disease process (only quicker drop in remission stage was observed, Fig. 1b).