TNF and psoriasis: Exosomes derived from human epidermal keratinocytes treated with psoriasis-related cytokines, such as IL-17A, IL-22, IFN-γ, and TNF-α, stimulate normal human neutrophils, followed by NF-κB and p38 MAPK signaling activation, leading to the production of TNF-α, IL-6, and IL-8, and NET formation [27].