ライム病ボレリアの抗原変異は,VMP型のシーケンスカセットの乱交的再結合によるものです
J R Zhang1, J M Hardham, A G Barbour
1Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston 77030, USA.
Cell
|April 18, 1997
まとめ
Borrelia burgdorferiは,表面のリポタンパク質VlsEを変化させるために複雑な遺伝システムを使用し,ライム病の際に免疫逃避を可能にします. この変異は,静かな遺伝子カセットが発現したVlsEに再結合し,何百万もの潜在的な変異を生み出します.
科学分野:
- 微生物学 微生物学とは
- 遺伝学 遺伝学とは
- 免疫学 免疫学とは
背景:
- ライム病は,スパイロケータBorrelia burgdorferiによって引き起こされます.
- Borrelia burgdorferiは,免疫逃避のためのメカニズムを有しています.
- 抗原的変異は,病原体の生存のための重要な戦略です.
研究 の 目的:
- Borrelia burgdorferi.の抗原変異に起因する遺伝システムを特定し,特徴づけること.
- VlsEの変動のメカニズムを理解するために.
- 宿主感染におけるこのシステムの役割を調査する.
主な方法:
- Borrelia burgdorferi B31.1.の遺伝子解析について
- 線形プラズミドlp28-1.1のvlsロカス識別について
- マウス感染時の再結合イベントの分析.
主要な成果:
- 線形プラズミドlp28-1.で新しい遺伝子システム (vls locus) が特定されました.
- 静かなvlsカセットのシーケンスが,中央のvlsE領域に再結合された.
- この再結合は,表面リポプロテインVlsE.の抗原的変異をもたらした.
結論:
- Borrelia burgdorferiは,VlsE抗原変異のための複雑な遺伝システムを採用しています.
- Vlsカセットの組み合わせ再組み合わせにより,広範な抗原多様性が生成されます.
- このメカニズムは,哺乳類の宿主における持続的な感染と免疫逃避に寄与する可能性がある.
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