Severe acute respiratory syndrome coronavirus 2 Spike protein (mRNA-1083) (SARS-CoV-2 S protein)

The SARS-CoV-2 Spike (S) protein is a large, trimeric class I fusion glycoprotein that is essential for the virus's ability to enter host cells. It consists of the S1 subunit, which facilitates attachment to the host cell surface via the Angiotensin-Converting Enzyme 2 (ACE2) receptor, and the S2 subunit, which mediates the fusion of the viral and host cell membranes (Wrapp et al., 2020; V'kovski et al., 2021). In the context of the mRNA-1083 combination vaccine, the mRNA-1083.1 component (often identified as mRNA-1283) encodes a specific, optimized version of the Spike protein, typically focusing on the receptor-binding domain (RBD) and N-terminal domain (NTD) of circulating variants like Omicron (Moderna, 2024). By inducing the endogenous production of this protein, the vaccine stimulates the immune system to generate neutralizing antibodies and cellular immunity. This target is the primary focus of most COVID-19 prophylactic interventions because its inhibition directly prevents viral infection. The Spike protein's structural plasticity and the emergence of new variants necessitate the continuous updating of the mRNA sequences used in vaccines like mRNA-1083 (Huang et al., 2020).

Other names

Spike glycoproteinS proteinSARS-CoV-2 surface glycoproteinmRNA-1083.1 encoded antigenmRNA-1283 encoded Spike protein

The mRNA-1083 vaccine delivers mRNA-1083.1 (a component encoding the SARS-CoV-2 Spike protein) into host cells via lipid nanoparticles. The host cell machinery translates this mRNA into the Spike protein, which is then presented on the cell surface. This triggers an immune response characterized by the production of neutralizing antibodies and the activation of T-cells, which provide protection against COVID-19 by preventing the virus from binding to host ACE2 receptors (Moderna, 2024; ClinicalTrials.gov, 2023).