Increased Circulatory Interleukin-17A Levels in Patients with Progressive and Leukotrichial Vitiligo

Abstract

Background. Vitiligo is a chronic condition characterized by skin depigmentation. Although not life-threatening, it significantly impacts quality of life. The pathophysiology of vitiligo remains poorly understood, and treatment options are limited. Mounting evidence supports the importance of autoreactive T cells and, particularly interleukin-17A- (IL-17A-) secreting Th17 cells, in vitiligo. IL-17A targeting has been proven successful in various inflammatory dermatological conditions, including psoriasis and lupus erythematosus. Objective. We evaluated the relationship between serum levels of IL-17A and the clinicopathological characteristics of Vietnamese vitiligo patients. Methods. In this cross-sectional study, we analyzed data from 52 nonsegmental vitiligo patients and 50 age- and sex-matched healthy individuals. Serum levels of IL-17A were measured using an enzyme-linked immunosorbent assay. We evaluated the correlation between IL-17A levels and clinical characteristics including leukotrichia, disease duration, vitiligo activity, and body surface area involvement. Results. Patients with progressive vitiligo had significantly higher IL-17A levels than patients with stable vitiligo ( $P$  = 0.014) or healthy individuals ( $P$  = 0.002). In addition, serum IL-17A levels were higher in vitiligo patients with leukotrichia than in patients without it ( $P$  = 0.04). Furthermore, serum IL-17A levels were negatively correlated with age (r = −0.39, $P$  = 0.004) and age of onset (r = −0.33, $P$  = 0.016) in vitiligo patients. Conclusions. Higher serum levels of IL-17A in patients with progressive vitiligo and leukotrichia suggest a potential role of IL-17A in melanocyte destruction in the epidermis and the follicular matrix.