期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2021
卷号:118
期号:50
DOI:10.1073/pnas.2112942118
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Significance
Developing molecules capable of binding to SARS-CoV-2 spike protein and inhibiting viral infection is of utmost importance for the detection and therapy of COVID-19. We have developed and engineered a serum-stable RNA aptamer specific for SARS-CoV-2 spike protein. We further show that scaffolding three aptamers together increases the binding efficiency to the low picomolar range and enables very efficient neutralization of SARS-CoV-2 infection in cells. The aptamer also shows high affinity for spike protein from variants of concern. Due to its small size and chemical stability, our aptamer holds potential as an alternative to antibodies and nanobodies targeting spike protein.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created an urgent need for new technologies to treat COVID-19. Here we report a 2′-fluoro protected RNA aptamer that binds with high affinity to the receptor binding domain (RBD) of SARS-CoV-2 spike protein, thereby preventing its interaction with the host receptor ACE2. A trimerized version of the RNA aptamer matching the three RBDs in each spike complex enhances binding affinity down to the low picomolar range. Binding mode and specificity for the aptamer–spike interaction is supported by biolayer interferometry, single-molecule fluorescence microscopy, and flow-induced dispersion analysis in vitro. Cell culture experiments using virus-like particles and live SARS-CoV-2 show that the aptamer and, to a larger extent, the trimeric aptamer can efficiently block viral infection at low concentration. Finally, the aptamer maintains its high binding affinity to spike from other circulating SARS-CoV-2 strains, suggesting that it could find widespread use for the detection and treatment of SARS-CoV-2 and emerging variants.
关键词:aptamer selection; SARS-CoV-2 targeting; aptamer multimerization; viral neutralization; spike protein