Microbiota and IL-33/31 Axis Linkage: Implications and Therapeutic Perspectives in Atopic Dermatitis and Psoriasis

Abstract

Microbiome dysbiosis and cytokine alternations are key features of atopic dermatitis (AD) and psoriasis (PsO), two of the most prevalent and burdensome pruritic skin conditions worldwide. Interleukin (IL)-33 and IL-31 have been recognized to be major players who act synergistically in the pathogenesis and maintenance of different chronic inflammatory conditions and pruritic skin disorders, including AD and PsO, and their potential role as therapeutic targets is being thoroughly investigated. The bidirectional interplay between dysbiosis and immunological changes has been extensively studied, but there is still debate regarding which of these two factors is the actual causative culprit behind the aetiopathological process that ultimately leads to AD and PsO. We conducted a literature review on the Pubmed database assessing articles of immunology, dermatology, microbiology and allergology with the aim to strengthen the hypothesis that dysbiosis is at the origin of the IL-33/IL-31 dysregulation that contributes to the pathogenesis of AD and PsO. Finally, we discussed the therapeutic options currently in development for the treatment of these skin conditions targeting IL-31, IL-33 and/or the microbiome.

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

“…Remarkably, the role of IL-33 in psoriasis should not be underscored. Several studies have pointed out that IL-33 is significantly increased at the lesion site and in the serum of psoriasis patients ( 161 – 164 ). IL-33, originating from keratinocyte secretion, triggers the expression of psoriasis-associated inflammatory factors and stimulates the progression of skin inflammation in psoriasis ( 165 , 166 ).…”

Staphylococcus aureus Adaptation to the Skin in Health and Persistent/Recurrent Infections

“…IL-31 has also been found at higher levels in lesional skin compared with non-lesional skin within the same patient [41]. The increased expression of IL-31 originates from the microbiota alteration and has an important role in pruritus, a condition that is the basis for scratching and favors the entrance of infecting microorganisms into the skin [42,43].…”