GPR15媒介のホーミングは,大腸の粘膜における免疫ホメオスタシスを制御する
Sangwon V Kim1, Wenkai V Xiang, Changsoo Kwak
1Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA.
Science (New York, N.Y.)
|May 11, 2013
まとめ
研究者らは,GPR15をT細胞が大腸へ送られるのを制御する重要な受容体として特定した. この発見は,炎症性腸疾患を理解し,調節性T細胞を調節することにより,粘膜の免疫耐性を促進するために重要である.
科学分野:
- 免疫学 免疫学とは
- 胃腸内科 胃腸内科
背景:
- リンパ球のホーミングは腸の免疫に不可欠ですが,炎症性腸疾患 (IBD) の重要な部位である大腸では理解されていない.
- リンパ球ホーミングに関する既存の研究は主に小腸に焦点を当てており,大腸に特化した免疫細胞の密輸に関する知識のギャップを残しています.
研究 の 目的:
- 免疫細胞を大腸内膜 (LILP) に誘導する特異的なT細胞ホーミング受容体を特定する.
- LILPへのT細胞ホーミングの調節におけるGPR15の役割と,粘膜の免疫耐性およびIBDに対するその影響について調査する.
主な方法:
- GPR15欠乏のマウスモデルを使用して,T細胞ホーミングと炎症に対する感受性への影響を評価しました.
- 腸内微生物群や変形成長因子β1.1.などの要因によってGPR15発現の調節を調査した.
- GPR15の機能的役割を評価するために,GPR15欠乏したマウスにおける規制性T細胞 (Treg) 移転の効果を分析した.
主要な成果:
- LILPへのT細胞ホーミング,特にFOXP3(+) 調節性T細胞 (Tregs) を媒介する重要な受容体としてGPR15を特定しました.
- GPR15の発現は腸内微生物群とTGF-β1の影響を受けるが,レチノ酸の影響は受けないことが実証された.
- GPR15欠乏症のマウスは大腸炎症を悪化させ,GPR15欠乏症のTregs.の移植により改善された.
結論:
- GPR15は,大腸のラミナ・プロパティのT細胞ホーミング受容体の1つである.
- GPR15は,大腸へのTreg流入を制御することによって,粘膜の免疫耐性を維持する上で重要な役割を果たします.
- GPR15をターゲットにすることで,炎症性腸疾患の管理のための治療戦略を提供することができます.
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