Analysis for melanocyte-specific T cells anargy system in autoimmune vitiligo

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K10154
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dermatology
• Research Institution: Osaka University
• Principal Investigator: Tanemura Atsushi 大阪大学, 医学系研究科, 講師 (50457016)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 白斑 / 自己免疫 / メラノサイト

Outline of Final Research Achievements

We aimed to clarify the T cell anergy status of melanocytes by focusing on the impaired equivalence of peripheral melanocyte-specific cytotoxic T cells and functional Tregs in patients with progressive vitiligo. The functional Tregs fraction and Melan-A-specific CD8+ T cells were simultaneously purified and co-cultured each other. The number of Melan-A-specific CD8+ T cells was then counted by FACS. As results, we demonstrated a reduced suppressive function of activated Tregs on Melan-A-specific CTLs in the circulating cells of vitiligo patients compared with healthy controls. This result suggests that T cell anergy with Tregs dysfunction may participate in the immune response to melanocytes in vitiligo patients. In contrast, there was no significant difference of the number and T cells subsets proportion between vitiligo and healthy circulating cells, therefore, we attempt to examine the specific phenotype of IFN-g producing CTLs in vitiligo skin lesion.

Free Research Field

白斑

Academic Significance and Societal Importance of the Research Achievements

白斑の病態は未だ完全に解明されておらず、本研究によりメラノサイトに対する自己免疫応答をキーワードとした病態の一端を実際の白斑症例を用いた実験で証明した。本研究のようにメラノサイト障害性T細胞を制御する制御性T細胞の機能に着目した研究はこれまで数少なく、今後白斑の新規創薬ターゲットになる可能性を示したことは、学術的・社会的意義があると考える。