SARS-CoV-2 spike protein receptor-binding domain (S RBD) (S RBD)

The SARS-CoV-2 spike protein receptor-binding domain (RBD) is a critical functional region of the S1 subunit of the viral spike glycoprotein, responsible for mediating the virus's entry into human cells. It achieves this by specifically binding to the human angiotensin-converting enzyme 2 (ACE2) receptor found on the surface of various cell types, particularly in the respiratory tract (UniProt P0DTC2; PubMed: 32155444). Given its pivotal role in the infection cycle, the RBD is the primary target for the host immune response and the development of therapeutic monoclonal antibodies. The drug combination of tixagevimab and cilgavimab (Evusheld) utilizes two human monoclonal antibodies that target different, non-overlapping sites on the RBD to neutralize the virus and provide pre-exposure prophylaxis against COVID-19 (FDA, 2021). However, the high mutation rate of the SARS-CoV-2 virus, particularly within the RBD, poses a significant challenge as new variants can emerge that evade neutralization by these antibodies, necessitating continuous monitoring and development of updated therapeutics (Nature, 2022).

Other names

Spike protein RBDS-RBDSARS-CoV-2 S1 RBDReceptor-binding domain of the spike protein

Neutralization of viral entry by blocking the interaction between the viral receptor-binding domain (RBD) and the host angiotensin-converting enzyme 2 (ACE2) receptor (NIH, 2023; FDA, 2022).