IL17A and immune system disorder: However, it can be expected to be unfavorable, because an upregulation of RORγt with elevated IL-17A and IL-22 levels has been proposed to play a role in immune disorders such as severe allergic asthma, psoriatic arthritis and UV-radiation induced promotion of skin cancer (Huang et al., 2020; Leijten et al., 2021; Lewis et al., 2021).