アポプトティック細胞とファゴサイトを結びつける因子の特定
Rikinari Hanayama1, Masato Tanaka, Keiko Miwa
1Department of Genetics, Osaka University Medical School, 2-2 Yamada-oka, Suita, Osaka, 565-0871, Japan.
Nature
|May 10, 2002
まとめ
乳脂肪球EGF因子8 (MFG-E8) は,死にゆく細胞とファゴサイトとの間の重要な橋渡し役を担っている. このタンパク質は,アポプトシス細胞の除去を促進し,組織損傷や炎症を予防します.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- バイオケミストリー バイオケミストリー
背景:
- アポプトティック細胞はファゴサイトによって除去され,組織ホメオスタシスを維持します.
- アポプトティック細胞のファゴサイトーシスは,特定の信号と受容体を伴う.
- アポプトティック細胞とファゴサイトを結びつける分子機構は,解明する必要がある.
研究 の 目的:
- ファゴサイトによるアポプトシス細胞の認識と吸収を媒介する要因を特定し,特徴づけること.
- エフェロサイトーシスにおけるミルク脂肪球-EGF-ファクター8 (MFG-E8) の役割を調査する.
主な方法:
- 活性化されたマクロファージにおけるMFG-E8の検出.
- フォスファディチルセリンの認識によるアポプトシス細胞へのMFG-E8結合の評価.
- アルファ ((v) ベータ ((3) インテグリンを使用したMFG-E8媒介のファゴサイトーシスの分析.
- 支配的な陰性MFG-E8変異体を使用したインビトロおよびインビボ阻害試験.
主要な成果:
- MFG-E8は,分泌されたグリコタンパク質で,活性化されたマクロファージによって生成されます.
- MFG-E8は,ホスファティジルセリンのようなアミノフォスフォリピドを認識することによって,特にアポプトシス細胞に結合します.
- MFG-E8は,アポプトシス細胞が,アルファ ((v) ベータ ((3) インテグリンを発現するファゴサイトに結合することを促進する.
- 変異したMFG-E8がアポプトシス細胞のファゴシトーシスをin vitroおよびin vivoで抑制しました.
結論:
- MFG-E8は,アポプトティック細胞とファゴサイトとの間の重要な分子リンクです.
- MFG-E8は,アポプトシス細胞のフォスファディチルセリンをファゴシートインテグリンに橋渡しすることでエフェロサイトーシスを媒介する.
- MFG-E8は,アポトーシス中に組織の完全性を維持する上で重要な役割を果たします.
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