既にある抗フラヴィウイルス免疫によって,ジカウイルスの病原性の強化
Susana V Bardina1, Paul Bunduc1, Shashank Tripathi1,2
1Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
Science (New York, N.Y.)
|April 1, 2017
まとめ
デング熱やウエストナイルウイルスの感染による抗体は,ジカウイルス病を悪化させる可能性があります. この抗体依存的増強はマウスの重症度と死亡率を高め,フラビウイルスワクチンの開発に注意を喚起します.
科学分野:
- ウイルス学
- 免疫学
- 感染症
背景:
- ジカウイルス (ZIKV) は,デング熱ウイルス (DENV) や西ナイルウイルス (WNV) のような他のフラビウイルスに特有な地域に広がり,世界的な健康問題となっている.
- 抗体依存増強 (ADE) は,あるフラビウイルスに先行的に曝露された場合,別のフラビウイルスに感染すると,より重症な疾患を引き起こす現象ですが,ZIKV感染におけるその役割は不明でした.
研究 の 目的:
- DENVとWNVの抗体がZIKVの感染を強めるかどうかを調査する.
- 交叉反応性抗体の存在におけるZIKV感染のインビボの結果を決定する.
主な方法:
- DENVおよびWNVに感染した個体からの回復期プラズマを使用して,ZIKVの感染性を評価するインビトロ試験.
- DENVまたはWNVの回復期プラズマをZIKV感受性のマウスに投与した in vivo試験.
主要な成果:
- DENVおよびWNVの感染から回復した血はZIKVの感染性を in vitroで有意に高めました.
- この増強は,Fcγ受容体への免疫グロブリンG (IgG) の結合によって媒介された.
- DENVまたはWNVの回復期プラズマを受けたマウスは,発熱,ウイルス血症,脊髄と丸のウイルス負荷,および死亡率の増加を示した.
結論:
- 関連フラビウイルスに対する既にある抗体による抗体依存増強 (ADE) は,最近のアウトブレイクで観察された重度のZIKV疾患の表れに寄与する可能性があります.
- これらの発見は,潜在的ADEを回避し,ワクチンの安全性を確保するために,フラビウイルスワクチンの開発に注意が必要であることを強調しています.
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