V因子のXa因子活性化は,凝固システムの開始において極めて重要です:の唾液タンパク質から学ぶこと
Tim J Schuijt1, Kamran Bakhtiari, Sirlei Daffre
1Center for Experimental and Molecular Medicine, University of Amsterdam, Meibergdreef 9, Room L01-145, 1105 AZ, Amsterdam, The Netherlands. T.J.Schuijt@outlook.com
Circulation
|July 3, 2013
まとめ
ティックは唾液タンパク質であるTIX-5を使用して,因子XA媒介の因子Vの活性化を阻害することによって,血液の凝結を抑制します. この発見は,凝固とと宿主の相互作用に関する新しい洞察を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- ヘモスタシス ヘモスタシスとは
背景:
- 血液凝固には,プロトロンビナーゼ複合体を形成するVa因子 (FVa) とXa因子 (FXa) が含まれる.
- 現在のモデルは,トロンビンがFVの活性化を開始することを示唆しているが,これは議論されている.
研究 の 目的:
- リコンビナントのダニの唾液タンパク質TIX-5の抗凝固剤の性質を調査する.
- ホストの凝固を阻害するTIX-5の分子機構を解明する.
主な方法:
- 再結合TIX-5.を製造した.
- 血,全血,浄化システムにおける抗凝固剤効果を研究した.
- TIX-5 免疫ウサギを用いて in vivo 効果を評価した.
主要な成果:
- TIX-5は,特にFVBドメインを標的として,FXa媒介のFV活性化を阻害します.
- FXa媒介によるFV活性化は,血と血液の凝固に不可欠である.
- TIX-5 免疫ウサギのティークの餌は損なわれ, in vivo の関連性を確認しています.
結論:
- ティックは,宿主の凝固を独特に抑制するためにTIX-5を使用します.
- 開始時にFXaが直接FVの活性化を媒介する改訂された凝固モデルを提案する.
- トロンビン媒介のFV活性化は,フィブリノゲンおよび阻害剤によって抑制されることがあります.
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