アルファ4インテグリンは,リンパ球の結合と生理学的流れの下の転移を媒介する
C Berlin1, R F Bargatze, J J Campbell
1Department of Pathology, Stanford University, California 94305.
Cell
|February 10, 1995
まとめ
アルファ4 (CD49d) インテグリンは,セレクトインとは独立して,シーアフロー下でリンパ球の粘着を開始します. これらのインテグリンは,β2インテグリンとは異なり,白血球の初期相互作用と結合に不可欠です.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- バイオフィジックス 生物物理学
背景:
- 白血球-内皮細胞の相互作用は,免疫反応にとって極めて重要です.
- セレクチンは,生理学的剪定下で白血球の転がりを開始し,インテグリン媒介による停止を先行する.
- ベータ2 (CD18) インテグリンは,中性粒子の粘着のためにセレクトインの関与を必要とします.
研究 の 目的:
- シャーフフロー下での白血球の粘着を開始するアルファ4 (CD49d) インテグリンの役割を調査する.
- アルファ4インテグリンがセレクトインとは独立して粘着を媒介できるかどうかを判断する.
- アルファ4インテグリン媒介付着のメカニズムを明らかにし,リガンド相互作用と地形表現を含む.
主な方法:
- リンパ球の結合と回転を評価するためのインビトロ切断フローアッセイ.
- リンパ球がlamina propria venulesに付着するインシット研究.
- スキャン電子顕微鏡で,リンパ性細胞のインテグリン分布を視覚化します.
主要な成果:
- アルファ4 (CD49d) インテグリンは,セレクトインの関与なしに,リンパ球の結合を開始します.
- アルファ4インテグリンリンガンド (MAdCAM-1,VCAM-1) は,ロールサポートとアクティベーション依存停止.
- アルファ4β7は,L-セレクチン独立のリンパ球結合を vivo で媒介する.
- アルファ4ベータ7はマイクロビリに濃縮され,初期接触を容易にし,ベータ2インテグリンは除外されています.
結論:
- アルファ4インテグリンは,ベータ2インテグリンではないが,フロー条件下で白血球の粘着を開始することができる.
- マイクロビルのアルファ4インテグリンの地形的な表示は,粘着を開始する役割に貢献します.
- これらの発見は,アルファ4インテグリンによって媒介されるリンパ球結合の開始のための明確なメカニズムを明らかにします.
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