S100B Is a Potential Disease Activity Marker in Nonsegmental Vitiligo.

Vitiligo is a chronic skin condition characterized by progressive depigmentation of the skin. S100B is a damage-associated molecular pattern protein expressed in melanocytes that has been proposed as a marker of melanocyte cytotoxicity. Although the use of S100B as a biomarker in melanoma is well established, to our knowledge its association with vitiligo activity has not yet been investigated. Here, we show that S100B serum levels were significantly increased in patients with active nonsegmental vitiligo and strongly correlated with the affected body surface area. Prospective follow-up showed a predictive value of serum S100B levels on disease progression. In vitro experiments using repeated freeze-thaw procedures showed an intracellular up-regulation of S100B in normal and vitiligo melanocytes before an extensive release in the environment. This phenomenon may explain the increased S100B serum values in the active phase of vitiligo. In a monobenzone-induced vitiligo mouse model we could show the potential of S100B inhibition as a therapeutic strategy in vitiligo. In conclusion, this report shows the possible use of S100B as a biomarker for disease activity in vitiligo. Our data suggest that this damage-associated molecular pattern protein could play a substantial role in the pathogenesis of vitiligo and may be a potential new target for treatment.