Treatment for autoimmune skin diseases with B10 cells

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K10153
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dermatology
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Fujimoto Noriki 滋賀医科大学, 医学部, 准教授 (50378460)
• Co-Investigator(Kenkyū-buntansha): 小笠原 一誠 滋賀医科大学, 医学部, 教授 (20169163) ; 田中 俊宏 滋賀医科大学, 医学部, 教授 (50188314)
• Research Collaborator: Takahashi Toshifumi ; Kabuto Miho ; Tsukamoto Yuko
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 抑制性B細胞 / B10 / IL-10 / CD26

Outline of Final Research Achievements

We could not detect molecules specific for IL-10-producing B cells called B10 cells. However, we found that B10 cells in peripheral blood mononuclear cells of patients of human autoimmune bullous diseases were associated with not pemphigoid but pemphigus. B10-cell level in pemphigus was not associated with disease severity but inversely correlated with the required dose of steroid for treatment. This study suggests that the lower production of IL-10 in CD9+ and CD27- B-cell subsets are associated with the pathogenesis of pemphigus. Moreover, we found that most of B10 cells were positive for CD26. So, we histologically evaluated the infiltration of CD26-positive cells in the skin lesions of DPP4 associated pemphigoid. From the results, we consider that more infiltrated CD26-positive cells are clinically associated with mild erythema and decreased peripheral counts of eosinophil in DPP4 associated pemphigus than in usual pemphigus.

Free Research Field

自己免疫性皮膚疾患

Academic Significance and Societal Importance of the Research Achievements

自己抗体により水疱を作る自己免疫性水疱症は天疱瘡と類天疱瘡に大別される。今回の研究成果により、天疱瘡においてはIL-10という免疫を抑制するサイトカインを産生するB細胞が病因に関与し、類天疱瘡と天疱瘡の病因は異なる可能性があることを示唆する結果を得た。また、糖尿病治療薬であるDPP4阻害薬による類天疱瘡ではCD26陽性B細胞が病態に関与していることが示唆された。これらにより、自己免疫性水疱症の治療にIL-10産生B細胞をターゲットにできる可能性を示した。