デンドリット細胞の成熟は,リソソームからプラズマ膜への逆行的なMHCクラスII輸送を誘発する
Amy Chow1, Derek Toomre, Wendy Garrett
1Department of Cell Biology and Section of Immunobiology, Ludwig Institute for Cancer Research, Yale University School of Medicine, 333 Cedar Street, PO Box 208002, New Haven, Connecticut 06520-8002, USA.
Nature
|August 29, 2002
まとめ
デンドリット細胞はTリンパ球に対して抗原を提示する. 刺激された dendritic 細胞は lysosomes からチューブルを形成し,免疫応答の開始のためにMHC II-ペプチド複合体を細胞表面に届けます.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
背景:
- Tリンパ球の活性化には,ペプチド抗原の認識が必要です.
- デンドリット細胞は,抗原のプレゼンテーションに不可欠です.
- メジャー・ヒストコンパティビリティ・コンプレックス・クラスII (MHC II) の分子は,このプロセスにおいて重要な役割を果たします.
研究 の 目的:
- MHC II-ペプチド複合体のトランスポート経路をデンドリット細胞で視覚化します.
- MHC IIの分子が,退廃性コンパートメントから細胞表面にどのように到達するかを理解する.
主な方法:
- dendritic 細胞のライブビデオ顕微鏡.
- 緑色光タンパク質 (GFP) でタグ付けされたMHC IIを発現する細胞を使用した.
主要な成果:
- 未成熟のデンドリット細胞は,MHC IIを後期エンドソーム/リソソームに貯蔵する.
- 刺激を受けたとき,デンドリット細胞は,エンドサイトーシスを下調調節し,共刺激分子を上調節する.
- 新しく形成されたMHC II-ペプチド複合体は,リンソーム管を通して細胞表面に輸送され,プラズマ膜と融合します.
結論:
- デンドリット細胞は,MHC II-ペプチド複合体をリゾソームから細胞表面に輸送するユニークなメカニズムを持っています.
- この経路は,Tリンパ球による適応性免疫応答の開始に不可欠です.
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