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Assessing Respiratory Immune Responses to Haemophilus Influenzae
Published on: June 29, 2021
エリトロマイシン耐性と,A群のストレプトコックスのヒト呼吸器細胞に侵入する能力との関連
B Facinelli1, C Spinaci, G Magi
1Institute of Microbiology, University of Ancona Medical School, Via Ranieri, Monte d'Ago, 60131, Ancona, Italy. b.facinelli@popsci.unian.it
Lancet (London, England)
|July 17, 2001
まとめ
エリトロマイシン耐性A群のストレプトコックは,増幅された細胞侵入とますます関連しています. この組み合わせにより,バクテリアはマクロリドやベータラクタムなどの抗生物質治療を回避することができます.
科学分野:
- 微生物学 微生物学とは
- 感染症 感染症は感染症です.
- 抗生物質耐性菌は,抗生物質耐性菌である.
背景:
- エリトロマイシンに対するA群のストレプトコック (GAS) 耐性菌は,ヨーロッパで増加しています.
- GASは,ヒトの呼吸器細胞内に侵入し,生き残ることができ,以前は強調されなかった特徴です.
- prtF1遺伝子は,GASが上皮細胞に侵入するために不可欠であり,マクロリド抗生物質はベータラクトームとは異なり,宿主細胞に浸透します.
研究 の 目的:
- prtF1遺伝子の存在を調査し,イタリアのグループAストレプトコックスの単離体における細胞侵入効率を評価する.
- エリトロマイシン耐性とGASのヒト呼吸器細胞を侵入する能力との関連を決定する.
主な方法:
- イタリアで炎を患った子供からエリトロマイシン耐性ガスの74個と感受性ガスの52個を検出した.
- トリプルディスクテストとPCRを用いて,エリトロマイシン耐性フェノタイプと耐性決定因子 (ermB, ermTR, mefA) を評価した.
- PCRによるprtF1遺伝子の存在を調査し,培養されたヒト呼吸器細胞におけるすべての株の細胞侵入効率を評価した.
主要な成果:
- 感受性菌株 (21%) に比べて,エリトロマイシン耐性菌株の有意に高い割合がprtF1陽性 (89%) であった.
- 高度に細胞侵入性のある孤立種 (>10%の侵入効率) は,感受性のある菌株 (10%) よりも,エリトロマイシン耐性菌株 (80%) の間で有意により一般的であった.
- prtF1 を欠いたすべてのエリトロマイシン耐性菌株は,M耐性フェノタイプを示した.
結論:
- エリトロマイシン耐性とA群の estreptococciの細胞侵襲性の増加の間に,予期せぬリンクが存在する.
- エリトロマイシン耐性と細胞内侵入能力の両方を備えたGAS株は,重大な臨床的懸念を提起しています.
- これらの二重特性菌株は,耐性のためにマクロリドによる治療を回避し,細胞内部位のためにβ-ラクトームを回避することがあります.
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