静脈内皮細胞によるIL-8のトランサイトーシスと表面表現

J Middleton¹, S Neil, J Wintle

¹Novartis Forschungsinstitut, Vienna, Austria.

Cell

|November 18, 1997

まとめ

IL-8のようなケモカインは,拡散ではなく,内部化とトランサイトーシス経由で内皮細胞を通して輸送されます. このプロセスは,炎症中の白血球の移住に不可欠です.

科学分野:

免疫学免疫学とは
細胞生物学細胞生物学
血管生物学血管生物学

背景:

ケモカインは,炎症性白血球の移住を媒介する.
組織に由来するケモカインは,循環中の白血球に到達するために,内皮細胞 (ECs) を横断しなければなりません.
以前の理解では,細胞間隙を通ってケモカインの拡散が示唆されていた.

研究の目的:

ケモキンが内皮細胞を通過するメカニズムを調査する.
ケモキンの輸送と白血球の募集における内皮細胞の役割を決定する.

主な方法:

電子顕微鏡を用いて,ケモカインIL-8と内皮細胞の相互作用を視覚化しました.
特定のケモカインドメインの機能的関連性は,in vivoで評価されました.

主要な成果:

ケモカインIL-8は,静脈ECによって光線外で内化され,光線表面にトランサイトスされます.
IL-8は,EC膜の白血球に提示され,しばしばEC投影と関連付けられます.
健全なIL-8のC端末は,EC結合,トランサイトシトーシス,およびプロエミグラトリー活動に不可欠である.

結論:

内皮細胞は,IL-8のようなケモカインを積極的に内部化し,トランサイトスします.
拡散というより,この活発な輸送メカニズムは,白血球の移住におけるケモカイン機能に極めて重要です.
IL-8のC末端ドメインは,その内皮細胞の相互作用と炎症機能において重要な役割を果たします.

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