IL-36 cytokines are increased in acne and hidradenitis suppurativa.

Interleukin (IL)-36 cytokines are new members of the IL-1 family, which include pro-inflammatory factors, IL-36α, IL-36β and IL-36γ, and a natural receptor antagonist IL-36Ra. Over recent years, much has been learned on their important functions in the regulation of immune response and, especially, on their role in many inflammatory skin diseases. However, to date, no data have been reported on their possible involvement in acne and hidradenitis suppurativa (HS). Here, we have shown that IL-36α, IL-36β, and IL-36γ are increased in lesional skin of acne and HS, highlighting their possible pathogenetic contribution to these two skin conditions. In contrast, IL-36Ra (the anti-inflammatory member of IL-36 sub-family) was increased just in psoriasis, suggesting that an imbalance in IL-36/IL36Ra functions could play a role in the phenotype of skin damage. One of the consequences of this imbalance may be the increased induction of IL-8 that we found higher in acne, HS, and ACD respect to psoriasis.