CD274 and psoriasis: Additionally, mouse model experiments focusing on Th1-mediated contact hypersensitivity, Th2-mediated atopic dermatitis (AD)-like inflammation, and Th17-mediated psoriasis-like dermatitis showed that PD-L1 knockout mice had accelerated Th1 and Th17 immune responses, whereas PD-L1 knockout mice demonstrated worse Th2 immune responses [36].