白血球結合分子-1 (LAM-1) の活性化による白血球移動の調節
O Spertini1, G S Kansas, J M Munro
1Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, Massachusetts.
Nature
|February 21, 1991
まとめ
白血球粘着分子-1 (LAM-1) の親和性は,活性化時に増加し,免疫応答中に白血球の組織への移住を制御します. これは,異なる白血球の種類が特定の方法でどのように移動するかを説明します.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 白血球の組織への移住は,病原体と炎症に対する宿主の防御に不可欠です.
- 白血球粘着分子-1 (LAM-1) は,白血球が内皮細胞と結合し,リンパ球をリンパ節に,中性粒子を炎症部位に導きます.
- LAM-1経由の血統特異白血球移動を制御するメカニズムは,共有表現にもかかわらず,不明のままでした.
研究 の 目的:
- 白血球の移動における系統特有の差異がどのように制御されるかを調査する.
- 白血球密輸におけるLAM-1親和度調節の役割を決定する.
主な方法:
- 活性化および非活性化リンパ球および中性粒子のリガンドであるPPMEに対するLAM-1の親和性を評価した.
- LAM-1-依存型リンパ球が,生理学的刺激による活性化に伴う高エンドセリアル静脈への結合を研究した.
主要な成果:
- 血統特異的刺激による白血球活性化は,炭水化物リガンドPPMEに対するLAM-1親和性を有意に増加させた.
- リンパ球の活性化により,LAM-1媒介による高内皮静脈への結合が強化された.
結論:
- 白血球活性化後のLAM-1親和度の一時的な変化は,白血球の移動を直接制御する.
- LAM-1親和性の調節は,免疫応答中に血統特異の白血球の密輸を制御するためのメカニズムを提供します.
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