Collapse of hair follicle immune privilege and immune check points

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K10238
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dermatology
• Research Institution: Hamamatsu University School of Medicine
• Principal Investigator: ITO Taisuke 浜松医科大学, 医学部, 准教授 (90293638)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 円形脱毛症 / 免疫チェックポイント / PD-1 / PD-L1

Outline of Final Research Achievements

In normal hair cycle, PD-L1 might be expressed on outer root sheath of anagen hair. Anagen hair has a possibility to escape from autoimmune attacking by the PD-L1 expression. Furthermore, infiltrating immune cells may downregulate the expression of PD-1 on cytotoxic T cells so that T cells is downregulate immune activity by PD-1/PD-L1 binding. On the other hand, in alopecia areata lesions, PD-1 expression was increased in and around hair bulbs. In dystrophic anagen hair, analysis of the expression of PD-L1 was difficult to measure correctly but slightly downregulated.

Free Research Field

皮膚科学

Academic Significance and Societal Importance of the Research Achievements

円形脱毛症の病態において毛包の免疫寛容の破綻は一つの重要な病因であり、その一つであるPD-1/PD-L1の関連を改名することは、この免疫チェックポイントを回復させることで脱毛症状の改善に結びつく可能性がある。過剰な免疫反応を抑制させるため、PD-L1発現をいかに上昇させるか、もしくは低下させない方法を見出すことが今後の治療につながっていくものと考えられる。