ヒトのマラリア寄生虫であるプラズモディウムビバックス (Plasmodium vivax) のサークムスポロゾイトタンパク質の異質性
R Rosenberg1, R A Wirtz, D E Lanar
1Department of Entomology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
まとめ
プラズモディウムビバックスマラリア・ circunsporozoite (CS) タンパク質におけるフェノタイプの異質性が発見されました. この変異は,CSタンパク質の一種を標的にするワクチンがすべてのマラリア株に対して保護しないことを意味します.
科学分野:
- 免疫学 免疫学とは
- 寄生虫学とは,寄生虫学である.
- 遺伝学 遺伝学とは
背景:
- プラズモディウム寄生虫の環胞体 (CS) タンパク質は,マラリアワクチン開発の主要な標的である.
- CSタンパク質のフェノタイプ的変異は,ワクチンの有効性に影響を与える可能性があります.
研究 の 目的:
- Plasmodium vivax CSのタンパク質におけるフェノタイプの異質性の程度を調査する.
主な方法:
- タイ西部の臨床マラリア症例の分析.
- モノクローナル抗体と免疫されたサルからの血清を用いた免疫学的測定法.
- CSタンパク質のリピート領域の遺伝子配列決定.
主要な成果:
- プラズモディウムビバックスマラリア症例の14%以上が,既知のタイプと免疫学的に異なるスポロゾイトを示した.
- これらの独特のスポロゾーイトは,他のP. vivax分離体や他のマラリア種に対する抗体と反応しなかった.
- 非反応性単離体におけるCSタンパク質遺伝子リピート配列は,公表された配列から有意な差異を示した.
結論:
- プラズモディウムビバックスCSタンパク質の繰り返し領域には,有意なフェノタイプ異質性が存在します.
- この異質性は,CSタンパク質の繰り返しに基づいた,普遍的に保護するP.vivaxワクチンの開発に課題をもたらします.
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