シングレット刺激酸素は白血球の抗菌作用の媒介体として作用する
Science (New York, N.Y.)
|October 25, 1974
まとめ
人間の白血球,特にポリモルフォン核白血球は,カロテノイドが欠けている細菌をより効果的に殺します. これは,カロテノイドによって消し去られたシングレット活性酸素が,重要な殺菌機構であることを示唆しています.
科学分野:
- 免疫学 免疫学とは
- 微生物学 微生物学とは
- バイオケミストリー バイオケミストリー
背景:
- 人間のポリモルフォ核白血球 (PMN) は,病原菌を殺害に関与する重要な免疫細胞です.
- カロテノイドは,反応性酸素種であるシングレット活性酸素を消し去ることが知られています.
- 以前の研究では,シングレット刺激酸素が,光力学的不活性化に作用することを示唆しています.
研究 の 目的:
- ヒトのPMNの殺菌活動におけるカロテノイドの役割を調査する.
- シングレット刺激酸素がPMN媒介による細菌殺しの媒介者かどうかを判断する.
主な方法:
- 人間のPMNによる無色なSarcina lutea変異株の殺戮と,カロテノイドを含む株の殺戮を比較した.
- シングレット刺激酸素に対するカロテノイドの保護効果を分析した.
主要な成果:
- 人間のPMNは,カロテノイドを含む株と比較して,無色なSarcina lutea変異体に対して,著しく高い殺戮率を示した.
- この差異的殺戮は,カロテノイドの既知のシングレット活性化酸素抑制特性と一致しています.
結論:
- カロテノイドは,PMN媒介による殺戮に対する細菌に対する保護的な利点を与える.
- シングレット刺激酸素は,ヒトポリモルフォ核白血球の殺菌作用の重要な媒介者である可能性が高い.
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