Neutralizing nanobodies bind SARS-CoV-2 spike RBD and block interaction with ACE2
Neutralizing nanobodies bind SARS-CoV-2 spike RBD and block interaction with ACE2
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DOI：
10.1038/s41594-020-0469-6
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发表时间：
2020-07-13
影响因子：
16.8
通讯作者：
Naismith, James H.
中科院分区：
文献类型：
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作者：
Huo, Jiangdong;Le Bas, Audrey;Naismith, James H.
结合SARS-CoV-2刺突RBD的两个纳米抗体被证明可以阻断与受体ACE 2的相互作用，从而中和病毒，并与抗体CR 3022产生叠加效应。SARS-CoV-2病毒比以前的冠状病毒更具传播性，引起的疾病比流感更严重。刺突蛋白的SARS-CoV-2受体结合结构域（RBD）与人血管紧张素转换酶2（ACE 2）受体结合，作为病毒进入细胞的前奏。使用天然美洲驼单域抗体文库和基于PCR的成熟，我们已经产生了两种密切相关的纳米抗体H11-D4和H11-H4，其结合RBD（K（D）分别为39和12 nM）并阻断其与ACE 2的相互作用。单颗粒冷冻-EM显示，两种纳米抗体都结合到刺突三聚体中的所有三种RBD。每个纳米抗体-RBD复合物的晶体结构揭示了两种纳米抗体如何识别相同的表位，其与ACE 2结合表面部分重叠，解释了RBD-ACE 2相互作用的阻断。纳米抗体-Fc融合物显示出对SARS-CoV-2的中和活性（H11-H4为4-6 nM，H11-D4为18 nM）和与SARS-CoV-1/2抗体CR 3022的相加中和。
Two nanobodies that bind SARS-CoV-2 spike RBD are shown to block interaction with receptor ACE2 and thus neutralize the virus, and have an additive effect with antibody CR3022.The SARS-CoV-2 virus is more transmissible than previous coronaviruses and causes a more serious illness than influenza. The SARS-CoV-2 receptor binding domain (RBD) of the spike protein binds to the human angiotensin-converting enzyme 2 (ACE2) receptor as a prelude to viral entry into the cell. Using a naive llama single-domain antibody library and PCR-based maturation, we have produced two closely related nanobodies, H11-D4 and H11-H4, that bind RBD (K(D)of 39 and 12 nM, respectively) and block its interaction with ACE2. Single-particle cryo-EM revealed that both nanobodies bind to all three RBDs in the spike trimer. Crystal structures of each nanobody-RBD complex revealed how both nanobodies recognize the same epitope, which partly overlaps with the ACE2 binding surface, explaining the blocking of the RBD-ACE2 interaction. Nanobody-Fc fusions showed neutralizing activity against SARS-CoV-2 (4-6 nM for H11-H4, 18 nM for H11-D4) and additive neutralization with the SARS-CoV-1/2 antibody CR3022.