Increased serum levels of interleukin-17 in patients with alopecia areata and non-segmental vitiligo

Abstract

Introduction: Alopecia areata (AA) and vitiligo are both skin diseases of autoimmune origin. AA is characterized by patchy hair loss primarily on the scalp but may involve other areas as well, while vitiligo is caused by the destruction of melanocytes and results in the appearance of white patches on any part of the body. Many facts indicate similar pathogenesis of these diseases. Both dermatoses are associated with frequent coexistence of other autoimmune diseases and share common genetic risk factors. Recent data support the theory of the involvement of IL-17 in the pathogenesis of both AA and vitiligo. Aim: To evaluate and compare the serum levels of interleukin (IL)-17 in patients with AA and non-segmental vitiligo (NSV). To assess whether the pattern of serum cytokine concentration can be associated with clinical details and activity of the disease. Material and methods: A cross-sectional study was conducted on 33 patients with AA, 30 patients with NSV, and 30 healthy controls. Serum levels of IL-17 were determined quantitatively by ELISA method. Results: Our analysis identified a systemic inflammatory signature associated with AA and NSV, characterized by elevated levels of IL-17. The levels of IL-17 did not differ significantly between AA patients and NSV patients. Conclusions: Our results show that AA and vitiligo may share common etiopathogenetic pathways, which suggests the potential of developing targeted therapies for both AA and vitiligo treatment. Imbalance of T cell subpopulations and complex systemic cytokine profiles may contribute to the pathogenesis of AA and vitiligo.

Baseline Levels of Circulating Inflammatory Biomarkers Stratify Patients with Vitiligo Who Significantly Repigment after Treatment with Ruxolitinib Cream

“…IL-17, a Th17 cytokine, mediates signaling through an NF-κB activator 1–dependent pathway that is independent of Jak signaling ( Gaffen, 2009 ). Serum levels of IL-17 were elevated in patients with vitiligo compared with those in healthy controls ( Karagün and Baysak, 2020 ; Tomaszewska et al., 2022 ) and were also positively correlated with disease duration, activity, and extent ( Czarnowicki et al., 2019 ; Sushama et al., 2019 ). Importantly, IL-17RA was upregulated in group 2 relative to that in group 1, indicating that baseline serum IL-17 levels may also have an inverse relationship with achieving clinical response.…”

Inheritance-Specific Dysregulation of Th1- and Th17-Associated Cytokines in Alopecia Areata

“…A developmental relationship between Th1 and Th17 cells, with Th1-induced IFNγ actually promoting the Th17 pathway, has been suggested [ 86 , 87 ]. There has been some indication of IL-17 activation in a CD8+ driven mouse model of AA [ 30 ], and increased serum levels of IL-17 have been found in a number of studies in AA patients when compared to controls [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 31 , 32 , 33 ]. Although the Th17 pathway has continued to be implicated in AA, a genetic underpinning for this has not been established and the potential familial dysregulation of the Th17 pathway in keeping with the autoimmune diathesis seen in families of AA patients has not been assessed to date.…”

“…Th17 cells have been shown to be relevant in several autoimmune diseases including inflammatory bowel disease, multiple sclerosis, psoriasis, eczema, rheumatoid arthritis, Sjögren’s syndrome, and vitiligo [ 13 , 14 , 15 ]. Specifically in AA, several studies on the role of Th17 cells in AA have shown increased serum levels of IL-17 in AA patients when compared to controls [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ] ( Table 1 ), and skewing towards the Th17 pathway [ 19 , 29 ]. These findings are supported by studies indicating IL-17 activation in a murine model of alopecia [ 30 ].…”

Serum Interleukin-17 in psoriatic patients implication for cardiovascular comorbidities

“…However, studies have reported that patients with alopecia areata don't show significant improvement with anti-IL-17 therapy secukinumab. Therefore, the contribution of Th17/IL-17 in the pathogenesis of alopecia areata is still controversial [23] .…”