An inflammatory triangle in psoriasis: TNF, type I IFNs and IL-17

Better Understanding the Immunopathogenesis of Psoriasis

“…Moreover, there is increased expression of several genes that participate in innate immune (and adaptive) responses [2,[4][5][6]. Activated keratinocytes, DC and macrophages produce various proinflammatory cytokines such as interleukin (IL) 1, IL-6, tumoral alpha necrosis factor (TNF-α) and interferon (INF) [1][2][3][4].…”

“…In the early development of lesions, it appears to be essential the activation of the plasmacytoid dendritic cells (pDC), producing INF-α [2][3][4]. INF-α and other proinflammatory cytokines (produced mainly by activated macrophages and keratinocytes) promote an excessive activation of the myeloid dermal dendritic cells (mDC), whose number is much increased in psoriatic plaques ( Figure 1) [1][2][3][4][5].…”

“…Initially there is a hyperactivation of IIS cells, especially keratinocytes, dermal Dendritic Cells (DC) and macrophages [1][2][3][4][5].…”

“…INF-α and other proinflammatory cytokines (produced mainly by activated macrophages and keratinocytes) promote an excessive activation of the myeloid dermal dendritic cells (mDC), whose number is much increased in psoriatic plaques ( Figure 1) [1][2][3][4][5]. [1][2][3][4][5].…”

“…In genetically predisposed individuals, environmental factors cause an exaggerated activation of the Innate Immune System (IIS) and the Adaptive Immune System (AIS), leading to excessive proliferation of keratinocytes and the appearance of skin lesions [1][2][3][4][5].…”