Mechanisms of Ulcerative Colitis Relapse Based on the Particularities of the Rectal Environment

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K08389
• 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: Kyushu University
• Principal Investigator: Ogino Haruei 九州大学, 大学病院, 助教 (80621705)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 潰瘍性大腸炎 / 再燃機序 / 直腸環境

Outline of Final Research Achievements

Ulcerative colitis (UC) is an intractable disease that repeatedly relapses and remits, but its cause remains unknown. UC is characterized by inflammation that begins from the rectum and spreads to the entire colon, but it is not well known why the inflammation extends from the rectum or what triggers the onset of the disease. In this study, we analyzed factors related to relapse in patients with UC in remission from various angles. We found no difference in the bacterial flora between the colon and rectum of patients with UC in remission who had achieved mucosal healing, but the mucosal barrier function was decreased only in the rectum. Furthermore, we found that the decreased mucosal barrier function was associated with increased expression of IL-1β, IL-6, and Claudin 2.

Free Research Field

炎症性腸疾患

Academic Significance and Societal Importance of the Research Achievements

動物実験腸炎モデルでは直腸のみに炎症を再現できるモデルが存在しないため、UCの病態を解明するためにはヒトにおける直腸の環境を評価するしかない。そこで、我々は寛解導入療法後に粘膜治癒が得られた状態に着目し、その病態を詳細に解析することで再燃の機序を解明出来るのではないかと考えた。直腸という特殊環境における免疫学的因子、腸内細菌叢、腸管上皮による粘膜バリア機能の相互関係を解析した研究は他になく我々の独自性があると考える。今回の研究によって、寛解中に再燃を来しにくい患者群を抽出することが出来れば、高額な寛解維持療法を中止する事が可能になり、医療経済における多大なメリットが得られると確信している。