Serum cytokine profiles predict response to systemic glucocorticoid in active vitiligo

Introduction:
Vitiligo is an immune-related skin disease. Cytokines regulate immune response and inflammation and are involved in the pathogenesis of vitiligo.

Aim:
To assess the serum levels of pro-inflammatory cytokines pre- and post- systemic glucocorticoid treatment in patients with active vitiligo.

Material and methods:
We measured serum cytokine levels using the enzyme-linked immunosorbent assay in 31 patients with active vitiligo before and after treatment. All patients received systemic glucocorticoid (compound betamethasone injection) in combination with topical halometasone cream and tacrolimus ointment for 3 months. Twenty healthy controls were also examined. The cytokines measured included TNF-a, IL-1b, IL-6, IFN-g, IL-2, IL-17, IL-10, IL-8, and CXCL10.

Results:
The serum levels of TNF-a, IL-1b, IL-6, IFN-g, IL-2, IL-17, IL-8, and CXCL10 were significantly higher, and levels of IL-10 were lower in vitiligo patients compared to controls. Additionally, serum IFN-g (r = 0.378; p = 0.036), IL-17 (r = 0.426; p = 0.017), and CXCL10 (r = 0.514; p = 0.003) showed a positive correlation with affected body surface area in vitiligo patients. After 3 months of systemic glucocorticoid treatment, the levels of IL-1b, IFN-g, IL-2, IL-17, and CXCL10 in responders were significantly decreased and nearly restored to normal levels. The IL-10 level was also increased in response to treatment. In contrast, the non-responder group had persistently high IL-6, IL-17, IL-8, and CXCL10 levels, and negligible changes in TNF-a, IL-1b, IFN-g, IL-2, and IL-10.

Conclusions:
Our study indicated that the levels of inflammatory cytokines were significantly ameliorated in the glucocorticoid responder group. Altered cell-mediated immunity may contribute to the resistance in vitiligo. The cytokines such as TNF-a, IL-1b, IFN-g and IL-2 could serve as therapeutic targets for managing glucocorticoid-resistant vitiligo.