細胞の活性化信号を伝達するチロシンを含むモチーフは,IgGのIII型受容体経由での内部化と抗原プレゼンテーションを決定します
S Amigorena1, J Salamero, J Davoust
1Laboratoire d'Immunologie Cellulaire et Clinique, INSERM U255, Institut Curie, Paris, France.
Nature
|July 23, 1992
まとめ
この研究は,FcガンマRIII受容体のガンマサブユニットがリガンド内化に不可欠であり,抗原プレゼンテーションの効率を高めることを明らかにしています. ガンマ鎖のチロシン残留物
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- FcガンマRIIやFcエプシロンRIのようなマルチメリック受容体は,リガンド結合と信号伝導のための特殊なサブユニットを持っています.
- マクロファージは,抗原の吸収,処理,Tリンパ球へのプレゼンテーションのためにFcガンマRIIアルファおよびガンマサブユニットを利用します.
- FcガンマRIII受容体は,免疫反応,特に抗原を呈現する細胞において重要な役割を果たします.
研究 の 目的:
- リガンド内部化と抗原プレゼンテーションにおけるFcガンマRIIIサブユニットの役割を調査する.
- 効率的な免疫複合体の吸収とプレゼンテーションに責任を負う特定のサブユニットとそのドメインを決定する.
- FcガンマRIIIガンマサブユニットが受容体媒介エンドサイトーシスに関与するシグナル伝達メカニズムを解明する.
主な方法:
- マウリンのFcガンマRIII細胞をFcガンマR陰性Bリンパ腫細胞に変異させる.
- FcガンマRIIIアルファおよびガンマサブユニットの機能を解剖するためにキメリック分子を利用する.
- ガンマ鎖のサイトプラズマ領域内のチロシン残留物の変異分析.
主要な成果:
- FcガンマRIIIは,迅速なリガンド内部化を媒介し,IgG複合体の抗原の抗原プレゼンテーションを強化する.
- リガンド結合アルファ鎖の細胞質ドメインは,内部化やプレゼンテーションには必要ありません.
- ガンマサブユニットは不可欠であり,その細胞質領域には免疫複合体の内部化と抗原プレゼンテーションに不可欠な特定のチロシン残留物があります.
結論:
- FcガンマRIIIガンマサブユニットには,受容体の内部化のための信号が含まれています.
- ガンマ鎖の細胞質領域のチロシン残留は,効率的な内部化と抗原プレゼンテーションに不可欠です.
- 関連する受容体連鎖,特にそのチロシンを含むモチーフは,細胞活性化だけでなく,多重メリク受容体内化に不可欠です.
関連する概念動画
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01:15Transcytosis of IgG
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01:26Antigens Involved in Adaptive Immunity
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Complete Antigens
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Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
01:28Diversity of Antigen Receptors
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01:24B Cell Activation and Differentiation
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