L-セレクチン媒介リンパ球がMAdCAM-1で転がっている
E L Berg1, L M McEvoy, C Berlin
1Department of Pathology, Stanford University, California 94305.
Nature
|December 16, 1993
まとめ
粘膜血管アドレシンMAdCAM-1は,L-セレクチンのための選択的リガンドであり,粘膜血管にリンパ球の回転をサポートします. この相互作用は,リンパ球の指向と粘膜組織における免疫監視に極めて重要です.
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:
- L-セレクチンはC型レクチンで,リンパ節とペイヤー斑へのリンパ球の輸送に不可欠です.
- また,免疫細胞の徴募における重要なプロセスである炎症した静脈と白血球の相互作用を媒介する.
- リンパ球の指向メカニズムを理解することは,炎症性および自己免疫疾患の標的治療の開発に不可欠です.
研究 の 目的:
- 粘膜血管アドレシンのMAdCAM-1がL-セレクトインのリガンドとして機能するかどうかを調査する.
- MAdCAM-1の結合特性と,剪定条件下におけるリンパ球結合におけるその役割の特徴.
- セレクトインおよびインテグリン媒介リンパ球相互作用の両方をサポートするMAdCAM-1の二重の役割を明らかにする.
主な方法:
- MAdCAM-1をメゼンテリックリンパ節と培養内皮腫細胞から分離した.
- 切断ストレス下でのL-セレクチン移植リンパ性細胞を用いた機能的粘着測定.
- MAdCAM-1の炭水化物構造の分析,シアル酸含量およびN-グリカナーゼ耐性を含む.
- アルファ4ベータ7インテグリンのためのリガンドとしてのMAdCAM-1の調査.
主要な成果:
- 粘膜血管アドレシンMAdCAM-1は,L-セレクトインの選択性リガンドとして特定されました.
- 培養細胞ではなく,メゼンテリックリンパ節からのMAdCAM-1は,L-セレクチン媒介のリンパ球粘着をシール下でサポートしました.
- この粘着は,MAdCAM-1上のN-グリカンゼ耐性,シアル酸を含む炭水化物を含む.
- リンパ球細胞は,MAdCAM-1で転がる行動を示し,炎上した静脈におけるセレクトイン依存の転がりを模倣した.
- MAdCAM-1は,アルファ4ベータ7インテグリンのためのリガンドとしても機能します.
結論:
- MAdCAM-1は,リンパ球の粘膜組織への帰着に関与する重要な粘着分子です.
- それはセレクトイン媒介のリンパ球の転移とインテグリン媒介の粘着をサポートし,リンパ球の停止をin vivoで容易にします.
- MAdCAM-1のユニークな特性は,粘膜部位における免疫細胞の監視に不可欠です.
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