腸内の多機能IgA+プラズマ細胞のフェノタイプを取得する
Jörg H Fritz1, Olga Lucia Rojas, Nathalie Simard
1Department of Immunology, University of Toronto, Toronto M5S 1A8, Canada.
Nature
|December 14, 2011
まとめ
腸内プラズマ細胞は,腫瘍死滅因子アルファ (TNF-α) や誘導性酸化窒素合成酵素 (iNOS) などの抗菌因子を産生する. この発見は,腸内ホメオスタシスを維持し,病原菌と戦うための新しい免疫適応を明らかにしています.
科学分野:
- 免疫学 免疫学とは
- 微生物学 微生物学とは
- 胃腸内科 胃腸内科
背景:
- 胃腸管は,微生物によって植民地化された,最大の粘膜表面を持っています.
- 微生物と免疫細胞の間のバランス (ホメオスタシス) を維持することは極めて重要です.
- ポリ反応性IGAは,このバランスの鍵であり,B細胞がプラズマ細胞に微分することによって生成されます.
研究 の 目的:
- 腸内のIgA分泌プラズマ細胞の追加の機能を調査する.
- IgAの産生を超えた新たな抗菌メカニズムを探求する.
主な方法:
- マウスにおけるIgA生成性プラズマ細胞の分析.
- 腸ストロマによるプラズマ細胞の微分化のインビトロ復習.
- 微生物共刺激実験について.
- 遺伝子消去研究 (B系細胞におけるTNF-αとiNOS).
主要な成果:
- マウスIgA(+) プラズマ細胞は,腫瘍死滅因子-α (TNF-α) と誘導性酸化窒素合成酵素 (iNOS) を生成する.
- これらの細胞は,モノサイト/グラヌロサイトマーカーを発現する.
- 微生物の共刺激は,この多機能的な現象型の開発に不可欠です.
- TNF-αとiNOSを削除すると,IgAの生産が低下し,腸内微生物群が変化し,病原体のクリアランスが低下します.
結論:
- 腸内IgA(+) プラズマ細胞は,新しい多機能的な現象型を持っています.
- このフェノタイプには,腸内ホメオスタシスに寄与する抗菌媒介体の生成が含まれています.
- 微生物の刺激が,この適応を促し,B系細胞の既知の保護的役割を拡大する.
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