T細胞の活性化後にプログラムされた細胞死に必要なFas ((CD95) /FasL相互作用)
1Arthritis Center, Boston University School of Medicine, Massachusetts 02118.
Nature
|February 2, 1995
まとめ
受容器のクロスリンクはT細胞を活性化し,細胞死につながる. このプロセスは,Fas結合体とFasを巻き込み,細胞死プログラムを誘発し,T細胞アポトーシスの重要な分子機構を明らかにします.
科学分野:
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- レセプタークロスリンクによるT細胞の活性化は,アポトーシスを引き起こします.
- この活性化誘発性細胞死 (AICD) を媒介する特定の遺伝子産物については,以前は特定されていなかった.
- AICDは新しいRNAとタンパク質の合成を必要とします.
研究 の 目的:
- レセプタークロスリンクによるT細胞死亡に起因する特定の遺伝子産物を特定する.
- 活性化誘発型T細胞死の原因となる分子メカニズムを解明する.
主な方法:
- T細胞ハイブリドオマを実験モデルに活用した.
- レセプタークロスリンクにおけるファス・リガンドとファス・アップレギュレーションの役割を調査した.
- 溶性ファス-免疫グロブリン融合タンパク質を用いて,ファス媒介シグナル伝達を遮断した.
主要な成果:
- 受容器のクロスリンクがFasリンガンドを誘導し,T細胞のFas発現を向上させることが判明しました.
- ファスリンガンドとファスの相互作用は,細胞死経路を活性化することが示されました.
- 溶解可能なFas-免疫グロブリン融合タンパク質は,細胞死を選択的に抑制したが,初期活性化には至らなかった.
結論:
- ファスリンガンドとファスは,活性化誘発型T細胞死亡を媒介する重要な死亡遺伝子産物である.
- Fas by Fas リガンドの関与は,AICDの核の分子メカニズムを表しています.
- これらの発見は,刺激後のT細胞アポトーシスにつながる経路を明確にします.
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