Role of airway mucosal IgA in allergic diseases

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K09629
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Respiratory organ internal medicine
• Research Institution: Teikyo University
• Principal Investigator: Suzukawa Maho 帝京大学, 医学部, 助手 (20453699)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: IgA / 肺線維芽細胞 / 特発性肺線維症 / サイトカイン / CD71

Outline of Final Research Achievements

The precise effects of IgA on lung fibroblasts remain unclear. This study aimed to elucidate how IgA activates human lung fibroblasts. Secretory IgA (sIgA) induced interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1 and granulocyte-macrophage colony-stimulating factor (GM-CSF) production by normal human lung fibroblasts (NHLFs). sIgA also promoted proliferation of NHLFs. Among known IgA receptors, NHLFs significantly expressed CD71. Immunohistochemistry revealed that sIgA is abundant in lung sections from patients with idiopathic pulmonary fibrosis (IPF). Our findings suggest that sIgA may promote human lung inflammation by activating human lung fibroblasts.

Free Research Field

呼吸器内科、免疫、アレルギー

Academic Significance and Societal Importance of the Research Achievements

気道粘膜を含め生体内において大量に存在する免疫グロブリンであり、抗原曝露の第一線に存在するIgAは、元来生体防御因子として重要視されてきたが、本研究から、肺の炎症を増強することで病原性役割があることが示唆された。本研究の結果を踏まえて、IgAが肺線維芽細胞を活性化する機構を明らかにできれば、IgAの役割の一部を標的とした予防あるいは治療戦略の確立につながる可能性がある。