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

The SARS-CoV-2 spike glycoprotein receptor-binding domain (RBD) is a critical functional unit within the S1 subunit of the viral spike protein, responsible for mediating infection by binding to the human angiotensin-converting enzyme 2 (ACE2) receptor (UniProt: P0DTC2). As the primary target for neutralizing antibodies, the RBD is the focus of most vaccine development and monoclonal antibody therapies designed to combat COVID-19 (PubMed: 32275855). Displaying the RBD as an antigen on the surface of Bacillus subtilis spores represents a specialized vaccine delivery platform intended to induce both systemic and mucosal immunity. Bacillus subtilis spores are highly resilient, non-pathogenic, and act as natural adjuvants, making them suitable for oral or intranasal administration without the need for a strict cold chain (PubMed: 33806144). This approach aims to stimulate local immune responses in the respiratory or gastrointestinal mucosa, potentially blocking the virus at its primary site of entry and providing a cost-effective alternative to traditional injectable vaccines (PubMed: 34516331).

Other names

SARS-CoV-2 S-RBDSpike protein receptor-binding domainS1-RBDSARS-CoV-2 RBD-spore displaySpore-displayed RBD antigen

Vaccines and therapeutic antibodies targeting the RBD aim to induce or provide neutralizing antibodies that competitively inhibit the interaction between the viral spike protein and the host Angiotensin-Converting Enzyme 2 (ACE2) receptor, thereby preventing viral attachment and entry into host cells (PubMed: 32275855).