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

The SARS-CoV-2 spike protein receptor-binding domain (RBD) is a critical region within the S1 subunit of the viral spike glycoprotein that mediates the virus's entry into host cells. It functions by specifically binding to the human Angiotensin-Converting Enzyme 2 (ACE2) receptor, which is widely expressed in the respiratory tract and other tissues (UniProt P0DTC2). This binding event is the first step of infection, triggering conformational changes that allow the virus to fuse with the host cell membrane (PubMed 32225176). Because the RBD is essential for viral attachment, it is the primary target for neutralizing antibodies generated by the immune system or administered as therapy. Imdevimab is a monoclonal antibody designed to bind to a specific, conserved epitope on the RBD, thereby sterically blocking the interaction with ACE2 and neutralizing the virus (FDA REGEN-COV Fact Sheet). Clinical use of drugs targeting the RBD has been effective in reducing viral load and preventing severe COVID-19 in high-risk patients. However, the RBD is subject to significant evolutionary pressure, leading to mutations that can result in viral escape, where the virus no longer binds effectively to certain therapeutic antibodies (PubMed 32540904). Consequently, the efficacy of RBD-targeting drugs like imdevimab must be continuously monitored against emerging SARS-CoV-2 variants.

Other names

Spike RBDS-RBDSARS-CoV-2 S protein RBDSARS-CoV-2 surface glycoprotein receptor-binding domainSARS-CoV-2 S1 RBD

Neutralization of viral infectivity by binding to the RBD and blocking its interaction with the human ACE2 receptor, thereby preventing viral entry into host cells.