改変されていないmRNAのCOVID-19ワクチンの非コーディング領域の最適化
Makda S Gebre1, Susanne Rauch2, Nicole Roth3
1Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Nature
|November 18, 2021
まとめ
第2世代のCureVac mRNAワクチン (CV2CoV) は,ヒト以外の霊長類における第1世代のCVnCoVワクチンと比較して,免疫性およびSARS-CoV-2に対する保護性が向上しています.
科学分野:
- ワクチン学
- 免疫学
- ウイルス学
背景:
- 重症急性呼吸器症候群コロナウイルス-2 (SARS-CoV-2) に対する第一世代のCureVac mRNAワクチン (CVnCoV) はヒト試験で評価されました.
- CV2CoVは,強化された抗原発現と改変された非コーディング領域を特徴とする最適化された第2世代のmRNAワクチンです.
研究 の 目的:
- CVnCoV と CV2CoV の免疫性および保護効果を比較する.
- SARS-CoV-2変種に対するCV2CoVの性能を評価し,BNT162b2ワクチンと比較する.
主な方法:
- シノモルグス・マカクは,CVnCoV,CV2CoV,または偽の2つの用量で免疫を受けました.
- 抗体位数,B細胞の応答,T細胞の応答を測定して免疫性を評価した.
- 保護効果はSARS-CoV-2 感染後に評価され,呼吸道でウイルスの負荷が測定されました.
主要な成果:
- CV2CoVは,CVnCoVと比較して,結合および中和抗体の位数,記憶B細胞およびT細胞の反応を著しく高めた.
- CV2CoVは,デルタを含むSARS-CoV-2変種に対する強力な中和抗体反応を示した.
- CV2CoVは,より低いウイルス負荷でSARS-CoV-2へのより強力な保護を提供し,マカクのBNT162b2と比較して免疫性であった.
結論:
- mRNAワクチンの非コーディング領域の最適化は,免疫性および保護効果を大幅に高めることができます.
- CV2CoVは,CVnCoVと比較して,SARS-CoV-2に対するより効果的なmRNAワクチン候補である.
- 抗体位数はSARS-CoV-2感染に対する保護効果と相関しています.
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