Oral communication, iL26

Official XXIst International Pigment Cell Conference website - 21-24 Sept 2011, Bordeaux - France | updated: September 04 2011

Monochromatic light for treatment of vitiligo

SPEAKER C.-C. E. Lan #whois submiter ?
AUTHOR(s) C.-C. E. Lan

BACKGROUND AND OBJECTIVE: Vitiligo is an acquired depigmentary dermatosis affecting at least 1% of the world population. Treatment for vitiligo is considered difficult and often results in unsatisfactory outcome. Phototherapy is an important treatment option for vitiligo, and currently, there is no consensus on how to optimally utilize the armamentaria available. Our laboratory has established several platforms to recapitulate the repigmentation processes of vitiligo in vitro. METHOD: Combining our clinical experiences with laboratory results, this presentation focuses on how to optimally use monochromic light (308 nm and 632.8 nm) for treatment of vitiligo. RESULTS: Clinically, excimer light has been observed to induce vitiligo repigmentation more rapidly than other UVB emitting devices. In our in vitro studies, we demonstrated that at similar doses, excimer light imparted different biological effects on primitive pigment cells as compared to its NBUVB counterpart. Both nuclear DNA and cytoplasmic tryptophan are recognized photoacceptors for UVB treatment. After irradiation at comparable doses, excimer light was able to induce primitive pigment cell differentiation through efficient activation of cytoplasmic pathway that involved formation of tryptophan derivate to activate aryl hydrocarbon receptor-related cascade while NBUVB failed to do so. Low-energy Helium-Neon laser is another monochromatic light source used to treat vitiligo especially for pediatric patients and anatomical regions not suitable for UV treatment. We showed that He-Ne laser is able to induce primitive pigment cell differentiation via mitochondrial-retrograde signaling. In addition, we also established treatment response predictive assay to select patients suitable for low-energy visible light treatment. Therefore, visible light may be considered as treatment of choice in certain clinical settings. CONCLUSION: In summary, monochromatic lights are important therapeutic modality for treating vitiligo. By elucidating the mechanisms involved in how lights at different wavelengths induce vitiligo repigmentation, physicians will be able to provide individualized phototherapy tailored to patients’ specific conditions.



Advertisement from our sponsor:
Astellas Pharma Worldwide

Université de Bordeaux 2 & Conseil Régional Aquitaine