Severe acute respiratory syndrome coronavirus 2 spike protein receptor-binding domain (SARS-CoV-2 RBD) (SARS-CoV-2 RBD)

The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein receptor-binding domain (RBD) is a critical region of the viral S1 subunit that mediates host cell attachment by binding to the human angiotensin-converting enzyme 2 (ACE2) receptor (UniProt: P0DTC2). This interaction occurs at the orthosteric site of the RBD, specifically the receptor-binding motif (RBM), and is the essential first step for viral entry and subsequent infection (PubMed: 32221306). Because of its pivotal role in the viral life cycle, the RBD is the primary target for neutralizing antibodies and the majority of COVID-19 vaccines (NIH: PMC7355128). Therapeutic monoclonal antibodies, such as bebtelovimab and sotrovimab, are designed to bind this domain with high affinity, thereby sterically blocking the virus from interacting with ACE2. However, the target is subject to high evolutionary pressure, leading to mutations that can result in viral escape and reduced efficacy of existing treatments (PubMed: 33688681). Monitoring anti-RBD antibody titers serves as a key biomarker for assessing both natural immunity and vaccine-induced protection.

Other names

Spike RBDS-RBDSARS-CoV-2 S protein RBDReceptor-binding domain of the spike proteinSARS-CoV-2 S1-RBDReceptor-binding motif (RBM)

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