表面ヒドロフォビンは,空気中の真菌胞子に対する免疫認識を妨げます
Vishukumar Aimanianda1, Jagadeesh Bayry, Silvia Bozza
1Unité des Aspergillus, Institut Pasteur, Paris F-75015, France.
Nature
|August 29, 2009
まとめ
空気中の真菌胞子には,免疫システムの活性化を防ぐ表面層があります. アスペルギルス・フミガトゥス (Aspergillus fumigatus) のようなコニディアのこの水害性ロドレット層は,免疫細胞からそれらをマスクし,炎症反応を防ぐ.
科学分野:
- 免疫学 免疫学とは
- 菌類学 菌類学とは
- 微生物学 微生物学とは
背景:
- 空気中の真菌胞子 (コニディア) は豊富で,アレルゲンを含んでいます.
- 空気中の真菌が常に免疫反応を誘発しない理由は不明です.
- 菌類の吸入は,有害な炎症反応につながる可能性があります.
研究 の 目的:
- 空気中の真菌胞子が免疫検出を回避するメカニズムを調査する.
- 菌類のコニディアにおける免疫逃避の原因となる成分を特定する.
- この成分を取り除くと免疫細胞が活性化するかどうかを判断する.
主な方法:
- デンドリット細胞とアルベオラマクロファージを用いたインビトロ試験.
- マウスの体内実験です.
- 表面層の化学的 (フッ化水素酸) および遺伝的 (DeltarodA変異体) 除去.
- 発芽による生物学的除去.
主要な成果:
- 休眠しているコニディアのRodaタンパク質で構成された水害性の"ロドレット層"は,免疫認識からそれらをマスクします.
- RodAタンパク質は免疫学的に無効であり,免疫細胞を in vitro や in vivo で活性化することができない.
- ロドレット層の除去 (化学的,遺伝的,または生物学的に) は,免疫活性化につながる.
結論:
- 空気中のキノココニディアの水害性ロドレット層は,免疫静音化に責任があります.
- このメカニズムは,本来の免疫細胞の継続的な活性化と,吸入時に有害な炎症反応を防ぐ.
- この層をターゲットにすることは,真菌に関連する免疫状態の管理に影響を及ぼす可能性があります.
関連する概念動画
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Overview
01:26Defense Mechanism Against Infection
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01:18Surface Membrane Barriers
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01:31Defense Against Bacterial Pathogens
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Phagocytes
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01:29Immune Response Against Viral Pathogens
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NK Cells
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NK Cells
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01:15Antifungal Agents
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