DNA released from dying cells acts as an inflammatory stimulus in psoriasis[48] and stimulates the receptors on certain dendritic cells, which in turn produce the cytokine interferon-??.[48] In response to these chemical messages from dendritic cells and T cells, keratinocytes also secrete cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor-??, which signal downstream inflamm