白血球は,生理学的フローレートでセレクトインを転がす:インテグリンを通じた粘着の前提と区別
1Center for Blood Research, Boston, Massachusetts 02115.
Cell
|May 31, 1991
まとめ
セレクチンに白血球が回転することは,炎症の重要な初期段階です. この研究は,流れ中の中性粒子のインテグリンベースの粘着強化に,セレクトイン媒介ローリングが必要であることを示しています.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- バイオフィジックス 生物物理学
背景:
- 炎症は,白血球が内皮細胞に転がり,CD62.2のようなセレクトインによって媒介される初期のイベントである.
- 内皮細胞への中性粒子の粘着は,免疫反応に不可欠ですが,特定の分子相互作用が必要です.
- 生理学的流れの条件下でこれらの相互作用を理解することは,炎症プロセスを理解するために不可欠です.
研究 の 目的:
- 流動下における中性粒子の粘着におけるセレクトイン媒介ローリングの役割を調査する.
- セレクトインとICAM-1の存在下における中性粒子の粘着に対するインテグリン (LFA-1,Mac-1) の寄与を決定する.
- 炎症時の安定した中性粒子の粘着につながる一連の出来事を明らかにする.
主な方法:
- 精製されたセレクトリンCD62とICAM-1で再構成された人工脂質二重層を用いたインビトロ実験.
- 中性粒子の回転と粘着を制御されたフロー条件下で研究し,後毛細血管を模倣する.
- 合成表面と相互作用する中性粒子の粘着強度と切断抵抗の評価,化学吸引剤の刺激となし.
主要な成果:
- 中性粒子は,生理学的切断ストレス下で,CD62を含む脂質二重層に転がっていることを示します.
- インテグリン媒介によるICAM-1への粘着は,生理学的剪定では最小でしたが,活性化された中性粒子の静的インキュベーションでは有意に増加しました.
- 化学吸引剤によって誘発されたインテグリンの活性化により,CD62とICAM-1の両方を含有するバイレイヤの回転中性粒子が停止し,粘着力が強化されたことが示されました.
結論:
- セレクチン依存型白血球の転移は,中性粒子のインテグリン媒介による粘着強化の前提条件である.
- ローリングから安定した粘着への移行は,インテグリンを活性化する化学吸引剤信号によって調節されます.
- この研究は,炎症中の中性粒子の募集を制御する連続的な分子イベントのインビトロ証拠を提供します.
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