A high-affinity RBD-targeting nanobody improves fusion partner's potency against SARS-CoV-2.
PLoS Pathog
; 17(3): e1009328, 2021 03.
Article
em En
| MEDLINE
| ID: mdl-33657135
ABSTRACT
A key step to the SARS-CoV-2 infection is the attachment of its Spike receptor-binding domain (S RBD) to the host receptor ACE2. Considerable research has been devoted to the development of neutralizing antibodies, including llama-derived single-chain nanobodies, to target the receptor-binding motif (RBM) and to block ACE2-RBD binding. Simple and effective strategies to increase potency are desirable for such studies when antibodies are only modestly effective. Here, we identify and characterize a high-affinity synthetic nanobody (sybody, SR31) as a fusion partner to improve the potency of RBM-antibodies. Crystallographic studies reveal that SR31 binds to RBD at a conserved and 'greasy' site distal to RBM. Although SR31 distorts RBD at the interface, it does not perturb the RBM conformation, hence displaying no neutralizing activities itself. However, fusing SR31 to two modestly neutralizing sybodies dramatically increases their affinity for RBD and neutralization activity against SARS-CoV-2 pseudovirus. Our work presents a tool protein and an efficient strategy to improve nanobody potency.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Anticorpos Neutralizantes
/
Anticorpos de Domínio Único
/
Enzima de Conversão de Angiotensina 2
/
SARS-CoV-2
/
Anticorpos Antivirais
Limite:
Humans
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article