Analysis and its application of cryptic-self antigens in patients with rhododendrol-induced leukoderma

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K15375
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Collagenous pathology/Allergology
• Research Institution: Saitama Medical University
• Principal Investigator: MATSUSHITA SHO 埼玉医科大学, 医学部, 教授 (50167649)
• Co-Investigator(Renkei-kenkyūsha): TSUCHIDA Tetuya 埼玉医科大学, 医学部, 教授 (70126126) ; NAKAMURA Kouichiro 埼玉医科大学, 医学部, 教授 (60175502) ; KAWANO Masaaki 埼玉医科大学, 医学部, 准教授 (30447528) ; TAKAGI Rie 埼玉医科大学, 医学部, 助手 (00569080)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: メラノーマ / ロドデノール / 白斑症 / 自己免疫 / T細胞 / チロシナーゼ / HLA / 隠ぺい自己抗原

Outline of Final Research Achievements

Rhododendrol, a phenolic compound contained in lightening/whitening cosmetics, can bind and inhibit tyrosinase, and was reported to induce leukoderma in Japan. Only 2% of the cosmetics users are affected, and tacrolimus is effective in the treatment. To test the hypothesis that the disease is an autoimmune disorder, short-term T-cell lines were established using PBMCs from 8 patients with human melanoma-associated and tyrosinase-derived synthetic peptides. Seven out of 8 patients were positive for HLA-DR4. Both class I- and class II-restricted and tyrosinase peptide-specific T-cell responses were observed. Immunization of mice with rhododendrol-treated and irradiated B16 melanoma cells successfully delayed the growth of melanoma cells in vivo. These observations collectively indicate that rhododendrol-induced leukoderma is an autoimmune disorder, with rhododendrol as an environmental factor and HLA-DR4 as a genetic factor. Rhododendrol might be effective in treating melanomas.

Free Research Field

医歯薬学