Autoantibodies in patients with autoimmune pancreatitis: its pathophysiological roles and clinical significance

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K07958
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 53010:Gastroenterology-related
• Research Institution: 株式会社関西メディカルネット(関西電力医学研究所)
• Principal Investigator: Chiba Tsutomu 株式会社関西メディカルネット(関西電力医学研究所), 関西電力医学研究所, 学術顧問 (30188487)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 自己免疫性膵炎 / 抗ラミニン511抗体 / 自己抗体

Outline of Final Research Achievements

We examined significance of anti-laminin 511 antibody in patients with autoimmune pancreatitis (AIP). In AIP patients with anti-laminin antibody, pancreas damage was more broad as compared to those without the antibody, and association of cancer and allergy was less prominent than in those without the antibody. A number of AIP patients without anti-laminin antibody had anti-integrin α6β1 antibody, and these were frequently associated with cancer or allergy. Nearly half of AIP patients had IgG4-related cholangitis, a half of which were positive for anti-laminin antibody. Some patients with type II AIP had anti-laminin antibody, and these patients were considered type I AIP. In contrast, some AIP patients with positive for neither antibody had UC. These patients were considered type II AIP.
Administration of IgG from AIP patients induced not only pancreatic but also biliary lesion in neonatal mice, but no pathology was found in lacrimal gland, salivary gland and in the kidney.

Free Research Field

消化器内科学

Academic Significance and Societal Importance of the Research Achievements

抗ラミニン511抗体を測定することによって、AIPの診断のみならず、原発性硬化性胆管炎とIgG4関連胆管炎を鑑別が可能となる。またI型、II型AIPの鑑別も容易になり、治療法の選択に役立つと思われた。一方、患者の抗体投与により病変が形成されることは、AIPの発症に自己抗体が関与することを示しており、このことは、今後の治療法開発に役立つと期待される。